diff --git a/ZelentsovAV/task1/bst.py b/ZelentsovAV/task1/bst.py new file mode 100644 index 0000000..47d1144 --- /dev/null +++ b/ZelentsovAV/task1/bst.py @@ -0,0 +1,79 @@ +def bst_insert(root, name, phone): + new_node = {'name': name, 'phone': phone, 'left': None, 'right': None} + + if root is None: + return new_node + + current = root + while True: + if name < current['name']: + if current['left'] is None: + current['left'] = new_node + break + else: + current = current['left'] + elif name > current['name']: + if current['right'] is None: + current['right'] = new_node + break + else: + current = current['right'] + else: + current['phone'] = phone + break + + return root + +def bst_find(root, name): #Итеративный поиск в BST + current = root + while current is not None: + if name == current['name']: + return current['phone'] + elif name < current['name']: + current = current['left'] + else: + current = current['right'] + return None + +def bst_find_min(root): #Поиск минимального узла + current = root + while current['left'] is not None: + current = current['left'] + return current + +def bst_delete(root, name): # Рекурсия только в глубину + if root is None: + return None + + if name < root['name']: + root['left'] = bst_delete(root['left'], name) + elif name > root['name']: + root['right'] = bst_delete(root['right'], name) + else: + if root['left'] is None: + return root['right'] + elif root['right'] is None: + return root['left'] + else: + min_node = bst_find_min(root['right']) + root['name'] = min_node['name'] + root['phone'] = min_node['phone'] + root['right'] = bst_delete(root['right'], min_node['name']) + return root + +def bst_list_all(root, records=None): #Возвращает отсортированные записи + if records is None: + records = [] + + stack = [] + current = root + + while stack or current: + while current is not None: + stack.append(current) + current = current['left'] + current = stack.pop() + records.append((current['name'], current['phone'])) + current = current['right'] + + return records \ No newline at end of file diff --git a/ZelentsovAV/task1/config.py b/ZelentsovAV/task1/config.py new file mode 100644 index 0000000..d1eb5b4 --- /dev/null +++ b/ZelentsovAV/task1/config.py @@ -0,0 +1,3 @@ +N = 10000 # Количество записей +REPEATS = 5 # Количество повторений каждого эксперимента +HASH_TABLE_SIZE = 1000 # Размер хеш-таблиц \ No newline at end of file diff --git a/ZelentsovAV/task1/docs/data/results.csv b/ZelentsovAV/task1/docs/data/results.csv new file mode 100644 index 0000000..466ba23 --- /dev/null +++ b/ZelentsovAV/task1/docs/data/results.csv @@ -0,0 +1,19 @@ +Структура,Режим,Операция,Повтор1,Повтор2,Повтор3,Повтор4,Повтор5,Среднее,Стд_откл +linkedlist,случайный,вставка,6.12412660010159,6.453428599983454,6.0159983998164535,5.846197799779475,6.687424399890006,6.225435159914196,0.3044218200660184 +linkedlist,случайный,поиск,0.04134450014680624,0.04073229990899563,0.042916799895465374,0.04113580007106066,0.05696159973740578,0.044618199951946734,0.006216087497843716 +linkedlist,случайный,удаление,0.026781500317156315,0.027109399437904358,0.030823000706732273,0.02719919942319393,0.03118100017309189,0.028618820011615753,0.001954103193777089 +linkedlist,отсортированный,вставка,6.631766900420189,5.748658500611782,5.798537000082433,6.062226499430835,5.308409399352968,5.909919659979641,0.43462320783889524 +linkedlist,отсортированный,поиск,0.006313499994575977,0.005670599639415741,0.005590200424194336,0.005645200610160828,0.005786299705505371,0.005801160074770451,0.0002640402924000638 +linkedlist,отсортированный,удаление,0.0005609998479485512,0.0005288999527692795,0.0005288999527692795,0.0006311992183327675,0.0005285991355776787,0.0005557196214795113,3.9747101397961354e-05 +hashtable,случайный,вставка,0.4039090992882848,0.43919940013438463,0.5127053996548057,0.4458825998008251,0.5722195003181696,0.47478319983929396,0.06009411868526661 +hashtable,случайный,поиск,0.0011500995606184006,0.0015127994120121002,0.0014458000659942627,0.0015266994014382362,0.0016105994582176208,0.001449199579656124,0.0001584761558930157 +hashtable,случайный,удаление,0.0006000008434057236,0.0006478000432252884,0.0006513996049761772,0.0006491998210549355,0.0006536999717354774,0.0006404200568795205,2.0308460750476644e-05 +hashtable,отсортированный,вставка,0.41475220024585724,0.36477189976722,0.4018732002004981,0.34626630041748285,0.3364391000941396,0.37282054014503957,0.030645843485620654 +hashtable,отсортированный,поиск,0.00014910008758306503,0.00021160021424293518,0.00014139991253614426,0.00013990048319101334,0.00014150049537420273,0.0001567002385854721,2.763741512756699e-05 +hashtable,отсортированный,удаление,0.00010520033538341522,0.00011090002954006195,9.95006412267685e-05,9.809993207454681e-05,9.940005838871002e-05,0.0001026201993227005,4.811371049160917e-06 +bst,случайный,вставка,0.02877839934080839,0.023240000009536743,0.023904399946331978,0.02267790026962757,0.02133959997445345,0.023988059908151626,0.0025394803712577006 +bst,случайный,поиск,0.00018490012735128403,0.00017419923096895218,0.0001809997484087944,0.0001767994835972786,0.0001687007024884224,0.00017711985856294632,5.569578481417004e-06 +bst,случайный,удаление,0.00012159999459981918,0.0001150006428360939,0.0001226002350449562,0.00011949986219406128,0.00011199992150068283,0.00011814013123512268,4.0316401567625745e-06 +bst,отсортированный,вставка,6.140015699900687,7.042814400047064,6.089983900077641,7.145617099478841,7.014688899740577,6.686623999848962,0.46902726732451255 +bst,отсортированный,поиск,0.0004746001213788986,0.0004603993147611618,0.0005575995892286301,0.0004612002521753311,0.0005747005343437195,0.0005056999623775482,4.9908362408772585e-05 +bst,отсортированный,удаление,0.0007436992600560188,0.0007255999371409416,0.0007277000695466995,0.0007218997925519943,0.0010781008750200272,0.0007993999868631362,0.00013954953359056988 diff --git a/ZelentsovAV/task1/docs/performance_chart.png b/ZelentsovAV/task1/docs/performance_chart.png new file mode 100644 index 0000000..fd663f1 Binary files /dev/null and b/ZelentsovAV/task1/docs/performance_chart.png differ diff --git a/ZelentsovAV/task1/docs/report.md b/ZelentsovAV/task1/docs/report.md new file mode 100644 index 0000000..2febb20 --- /dev/null +++ b/ZelentsovAV/task1/docs/report.md @@ -0,0 +1,85 @@ +# Отчёт по лабораторной работе + +## Цель работы + +Реализовать три структуры данных «с нуля» (связный список, хеш-таблица, двоичное дерево поиска), применить их для хранения записей телефонного справочника и экспериментально сравнить производительность основных операций. + +## Параметры эксперимента + +- Количество записей: 10000 +- Количество повторов каждого теста: 5 +- Размер хеш-таблицы: 1000 корзин + +## Результаты экспериментов + +### 1. Связный список + +| Режим | Вставка (сек) | Поиск (сек) | Удаление (сек) | +|-------|---------------|-------------|----------------| +| Случайный | 6.2254 | 0.0446 | 0.0286 | +| Отсортированный | 5.9099 | 0.0058 | 0.0006 | + +### 2. Хеш-таблица + +| Режим | Вставка (сек) | Поиск (сек) | Удаление (сек) | +|-------|---------------|-------------|----------------| +| Случайный | 0.4748 | 0.0014 | 0.0006 | +| Отсортированный | 0.3728 | 0.0002 | 0.0001 | + +### 3. Двоичное дерево поиска (BST) + +| Режим | Вставка (сек) | Поиск (сек) | Удаление (сек) | +|-------|---------------|-------------|----------------| +| Случайный | 0.0240 | 0.0002 | 0.0001 | +| Отсортированный | 6.6866 | 0.0005 | 0.0008 | + +## Анализ результатов + +### 1. Влияние порядка данных на BST +При добавлении уже отсортированных элементов BST вырождается в линейную структуру — сложность падает с O(log n) до O(n). +Время вставки выросло с 0.0240 до 6.6866 секунд — замедление в 278.7 раза. + +### 2. Почему хеш-таблица не чувствительна к порядку + +Хеш-функция равномерно распределяет ключи по корзинам независимо от их исходного порядка. Поэтому последовательность добавления практически не влияет на производительность. +Сравнение случайного и упорядоченного ввода: +- Случайный режим: 0.4748 с +- Упорядоченный режим: 0.3728 с +- Различие: 0.79 + +### 3. Почему связный список медленный при поиске + +Поиск в связном списке требует линейного обхода O(n) — структура не поддерживает произвольный доступ. Это делает его непригодным для крупных справочников, где нужен быстрый поиск по ключу. + +Сравнение скорости поиска на случайных данных: +- LinkedList: 0.0446 сек +- HashTable: 0.0014 сек (преимущество в 30.8) +- BST: 0.0002 сек + +### 4. Сравнение удаления + +| Структура | Сложность | Время на 50 удалений (случайные данные) | +|-----------|-----------|------------------------------------------| +| Связный список | O(n) | 0.0286 сек| +| Хеш-таблица | O(1) в среднем | 0.0006 сек | +| BST | O(log n) в среднем | 0.0001 сек | + +## Вывод: + +| Задача | Рекомендация | Почему | +|--------|-------------|--------| +| Частый поиск | Хеш-таблица | O(1) в среднем, не зависит от порядка | +| Частые вставки/удаления | Хеш-таблица | Амортизированное O(1) | +| Нужен отсортированный вывод | Сбалансированное дерево (AVL/Red-Black) | In-order обход даёт сортировку | +| Мало данных (<100 элементов) | Связный список или массив | Простота, накладные расходы не оправданы | +| Последовательный доступ (очередь/стек) | Связный список | Вставка/удаление в начало/конец за O(1) | + +## Заключение +Проведённый эксперимент подтверждает теоретические оценки сложности: + +1. **Небалансированное BST это плохой выбор** при работе с реальными данными, которые могут оказаться упорядоченными. Деградация до O(n) делает его непригодным для надёжных систем. + +2. **Хеш-таблица показывает стабильные результаты** вне зависимости от порядка входных данных — ключевое преимущество для телефонного справочника с произвольными именами абонентов. + +3. **Связный список — нишевый инструмент**, эффективный только при работе с малыми объёмами данных. + diff --git a/ZelentsovAV/task1/experiment.py b/ZelentsovAV/task1/experiment.py new file mode 100644 index 0000000..505d5b2 --- /dev/null +++ b/ZelentsovAV/task1/experiment.py @@ -0,0 +1,90 @@ +import time +import numpy as np +from linkedlist import ll_insert, ll_find, ll_delete +from hashtable import ht_create, ht_insert, ht_find, ht_delete +from bst import bst_insert, bst_find, bst_delete + +def measure_insert(records, struct_type, params=None): #Замер времени вставки всех записей + start = time.perf_counter() + + if struct_type == 'linkedlist': + head = None + for name, phone in records: + head = ll_insert(head, name, phone) + result = head + + elif struct_type == 'hashtable': + size = params.get('size', 1000) if params else 1000 + buckets = ht_create(size) + for name, phone in records: + ht_insert(buckets, name, phone) + result = buckets + + elif struct_type == 'bst': + root = None + for name, phone in records: + root = bst_insert(root, name, phone) + result = root + + end = time.perf_counter() + return end - start, result + +def measure_find(structure, names_to_find, struct_type): #Замер времени поиска записей + start = time.perf_counter() + + for name in names_to_find: + if struct_type == 'linkedlist': + ll_find(structure, name) + elif struct_type == 'hashtable': + ht_find(structure, name) + elif struct_type == 'bst': + bst_find(structure, name) + + end = time.perf_counter() + return end - start + +def measure_delete(structure, names_to_delete, struct_type): #Замер времени удаления записей + start = time.perf_counter() + + for name in names_to_delete: + if struct_type == 'linkedlist': + structure = ll_delete(structure, name) + elif struct_type == 'hashtable': + ht_delete(structure, name) + elif struct_type == 'bst': + structure = bst_delete(structure, name) + + end = time.perf_counter() + return end - start, structure + +def run_single_experiment(struct_type, mode, data_records, names_to_find, names_to_delete, repeats, params=None): #Запуск одного эксперимента + insert_times = [] + find_times = [] + delete_times = [] + + for i in range(repeats): + if struct_type == 'hashtable': + insert_time, structure = measure_insert(data_records, struct_type, params) + else: + insert_time, structure = measure_insert(data_records, struct_type) + insert_times.append(insert_time) + + find_time = measure_find(structure, names_to_find, struct_type) + find_times.append(find_time) + + delete_time, structure = measure_delete(structure, names_to_delete, struct_type) + delete_times.append(delete_time) + + return { + 'structure': struct_type, + 'mode': mode, + 'insert_mean': np.mean(insert_times), + 'insert_std': np.std(insert_times), + 'insert_all': insert_times, + 'find_mean': np.mean(find_times), + 'find_std': np.std(find_times), + 'find_all': find_times, + 'delete_mean': np.mean(delete_times), + 'delete_std': np.std(delete_times), + 'delete_all': delete_times + } \ No newline at end of file diff --git a/ZelentsovAV/task1/generator.py b/ZelentsovAV/task1/generator.py new file mode 100644 index 0000000..3691bec --- /dev/null +++ b/ZelentsovAV/task1/generator.py @@ -0,0 +1,18 @@ +import random + +def generate_test_data(N): #Генерирует N записей с именами User_00000 ... User_N-1 + records = [(f"User_{i:05d}", f"+7-999-{i:05d}") for i in range(N)] + + records_shuffled = records.copy() + random.shuffle(records_shuffled) + + records_sorted = sorted(records, key=lambda x: x[0]) + + return records, records_shuffled, records_sorted + +def get_names_for_operations(records, num_find=100, num_delete=50, num_nonexistent=10): #Подготавливает имена для операций поиска и удаления + existing_names = [name for name, _ in records[:num_find + num_delete]] + names_to_find = existing_names[:num_find] + [f"None_{i}" for i in range(num_nonexistent)] + names_to_delete = existing_names[num_find:num_find + num_delete] + + return names_to_find, names_to_delete \ No newline at end of file diff --git a/ZelentsovAV/task1/hashtable.py b/ZelentsovAV/task1/hashtable.py new file mode 100644 index 0000000..363f9f1 --- /dev/null +++ b/ZelentsovAV/task1/hashtable.py @@ -0,0 +1,29 @@ +from linkedlist import ll_insert, ll_find, ll_delete, ll_list_all + +def hash_function(name, size): + return sum(ord(c) for c in name) % size + +def ht_create(size): + return [None] * size + +def ht_insert(buckets, name, phone): + index = hash_function(name, len(buckets)) + buckets[index] = ll_insert(buckets[index], name, phone) + +def ht_find(buckets, name): + index = hash_function(name, len(buckets)) + return ll_find(buckets[index], name) + +def ht_delete(buckets, name): + index = hash_function(name, len(buckets)) + buckets[index] = ll_delete(buckets[index], name) + +def ht_list_all(buckets): + records = [] + for bucket in buckets: + current = bucket + while current is not None: + records.append((current['name'], current['phone'])) + current = current['next'] + records.sort(key=lambda x: x[0]) + return records \ No newline at end of file diff --git a/ZelentsovAV/task1/linkedlist.py b/ZelentsovAV/task1/linkedlist.py new file mode 100644 index 0000000..d83ca7d --- /dev/null +++ b/ZelentsovAV/task1/linkedlist.py @@ -0,0 +1,47 @@ +def ll_insert(head, name, phone): #Oбновление записи в связном списке + if head is None: + return {'name': name, 'phone': phone, 'next': None} + current = head + while current is not None: + if current['name'] == name: + current['phone'] = phone + return head + current = current['next'] + new_node = {'name': name, 'phone': phone, 'next': None} + current = head + while current['next'] is not None: + current = current['next'] + current['next'] = new_node + return head + +def ll_find(head, name): #Поиск телефона по имени + current = head + while current is not None: + if current['name'] == name: + return current['phone'] + current = current['next'] + return None + +def ll_delete(head, name): #Удаление записи по имени + if head is None: + return None + + if head['name'] == name: + return head['next'] + + current = head + while current['next'] is not None: + if current['next']['name'] == name: + current['next'] = current['next']['next'] + return head + current = current['next'] + return head + +def ll_list_all(head): #Сбор всех записей и сортировка по имени + records = [] + current = head + while current is not None: + records.append((current['name'], current['phone'])) + current = current['next'] + records.sort(key=lambda x: x[0]) + return records \ No newline at end of file diff --git a/ZelentsovAV/task1/main.py b/ZelentsovAV/task1/main.py new file mode 100644 index 0000000..6d34384 --- /dev/null +++ b/ZelentsovAV/task1/main.py @@ -0,0 +1,51 @@ +from config import N, REPEATS, HASH_TABLE_SIZE +from generator import generate_test_data, get_names_for_operations +from experiment import run_single_experiment +from rezults import save_to_csv, plot_results, print_analysis, save_report_md + +def main(): + print(f"Количество записей: {N}") + print(f"Количество повторов: {REPEATS}") + print(f"Размер хеш-таблицы: {HASH_TABLE_SIZE}") + print() + + records, records_shuffled, records_sorted = generate_test_data(N) + names_to_find, names_to_delete = get_names_for_operations(records) + + experiments = [ + ('linkedlist', 'случайный', records_shuffled), + ('linkedlist', 'отсортированный', records_sorted), + ('hashtable', 'случайный', records_shuffled), + ('hashtable', 'отсортированный', records_sorted), + ('bst', 'случайный', records_shuffled), + ('bst', 'отсортированный', records_sorted), + ] + + results = [] + + for struct_type, mode, data_records in experiments: + print(f"Тестирование: {struct_type} - {mode}") + + params = {'size': HASH_TABLE_SIZE} if struct_type == 'hashtable' else None + + result = run_single_experiment( + struct_type, mode, data_records, + names_to_find, names_to_delete, + REPEATS, params + ) + + results.append(result) + + print(f" Insert: {result['insert_mean']:.4f} ± {result['insert_std']:.4f} sec") + print(f" Find: {result['find_mean']:.4f} ± {result['find_std']:.4f} sec") + print(f" Delete: {result['delete_mean']:.4f} ± {result['delete_std']:.4f} sec") + print() + + save_to_csv(results) + plot_results(results) + save_report_md(results) + print_analysis(results) + + +if __name__ == "__main__": + main() \ No newline at end of file diff --git a/ZelentsovAV/task1/rezults.py b/ZelentsovAV/task1/rezults.py new file mode 100644 index 0000000..99ab814 --- /dev/null +++ b/ZelentsovAV/task1/rezults.py @@ -0,0 +1,288 @@ +import csv +import os +import numpy as np +from matplotlib import pyplot as plt + +def ensure_directories(): + os.makedirs('docs/data', exist_ok=True) + +def save_to_csv(results, filename="docs/data/results.csv"): + ensure_directories() + + with open(filename, 'w', newline='', encoding='utf-8') as f: + writer = csv.writer(f) + writer.writerow(['Структура', 'Режим', 'Операция', + 'Повтор1', 'Повтор2', 'Повтор3', 'Повтор4', 'Повтор5', + 'Среднее', 'Стд_откл']) + + for res in results: + struct_name = res['structure'] + mode = res['mode'] + + for op, times, mean, std in [ + ('вставка', res['insert_all'], res['insert_mean'], res['insert_std']), + ('поиск', res['find_all'], res['find_mean'], res['find_std']), + ('удаление', res['delete_all'], res['delete_mean'], res['delete_std']) + ]: + row = [struct_name, mode, op] + times + [mean, std] + writer.writerow(row) + +def plot_results(results, filename="docs/performance_chart.png"): + ensure_directories() + struct_names = { + 'linkedlist': 'LinkedList', + 'hashtable': 'HashTable', + 'bst': 'BST' + } + + operations = ['insert', 'find', 'delete'] + op_names = {'insert': 'Вставка', 'find': 'Поиск', 'delete': 'Удаление'} + random_data = {} + sorted_data = {} + + for res in results: + struct_name = struct_names.get(res['structure'], res['structure']) + mode = res['mode'] + + if mode == 'случайный': + random_data[struct_name] = { + 'insert': res['insert_mean'], + 'find': res['find_mean'], + 'delete': res['delete_mean'] + } + else: + sorted_data[struct_name] = { + 'insert': res['insert_mean'], + 'find': res['find_mean'], + 'delete': res['delete_mean'] + } + + structure_order = ['LinkedList', 'HashTable', 'BST'] + + fig, axes = plt.subplots(1, 3, figsize=(15, 5)) + + for idx, op in enumerate(operations): + ax = axes[idx] + + x = np.arange(len(structure_order)) + width = 0.35 + + random_means = [] + sorted_means = [] + + for struct in structure_order: + if struct in random_data: + random_means.append(random_data[struct][op]) + else: + random_means.append(0) + + if struct in sorted_data: + sorted_means.append(sorted_data[struct][op]) + else: + sorted_means.append(0) + + if not random_means and not sorted_means: + print(f" Нет данных для операции {op}") + continue + + bars1 = ax.bar(x - width/2, random_means, width, + label='Случайный порядок', color='skyblue') + bars2 = ax.bar(x + width/2, sorted_means, width, + label='Отсортированный порядок', color='salmon') + + ax.set_xlabel('Структура данных') + ax.set_ylabel('Время (секунды)') + ax.set_title(f'{op_names.get(op, op)}') + ax.set_xticks(x) + ax.set_xticklabels(structure_order) + ax.legend() + + for bar in bars1 + bars2: + height = bar.get_height() + if height > 0: + ax.annotate(f'{height:.3f}', + xy=(bar.get_x() + bar.get_width() / 2, height), + xytext=(0, 3), textcoords="offset points", + ha='center', va='bottom', fontsize=8) + + plt.tight_layout() + plt.savefig(filename, dpi=150) + plt.show() + +def save_report_md(results, filename="docs/report.md"): + ensure_directories() + + results_dict = {} + for res in results: + key = (res['structure'], res['mode']) + results_dict[key] = res + + def get_val(struct, mode, field): + key = (struct, mode) + if key in results_dict:return results_dict[key][field] + return 0.0 + + ll_random_insert = get_val('linkedlist', 'случайный', 'insert_mean') + ll_random_find = get_val('linkedlist', 'случайный', 'find_mean') + ll_random_delete = get_val('linkedlist', 'случайный', 'delete_mean') + ll_sorted_insert = get_val('linkedlist', 'отсортированный', 'insert_mean') + ll_sorted_find = get_val('linkedlist', 'отсортированный', 'find_mean') + ll_sorted_delete = get_val('linkedlist', 'отсортированный', 'delete_mean') + + ht_random_insert = get_val('hashtable', 'случайный', 'insert_mean') + ht_random_find = get_val('hashtable', 'случайный', 'find_mean') + ht_random_delete = get_val('hashtable', 'случайный', 'delete_mean') + ht_sorted_insert = get_val('hashtable', 'отсортированный', 'insert_mean') + ht_sorted_find = get_val('hashtable', 'отсортированный', 'find_mean') + ht_sorted_delete = get_val('hashtable', 'отсортированный', 'delete_mean') + + bst_random_insert = get_val('bst', 'случайный', 'insert_mean') + bst_random_find = get_val('bst', 'случайный', 'find_mean') + bst_random_delete = get_val('bst', 'случайный', 'delete_mean') + bst_sorted_insert = get_val('bst', 'отсортированный', 'insert_mean') + bst_sorted_find = get_val('bst', 'отсортированный', 'find_mean') + bst_sorted_delete = get_val('bst', 'отсортированный', 'delete_mean') + + from datetime import datetime + + report_content = f"""# Отчёт по лабораторной работе + +## Цель работы + +Реализовать три структуры данных «с нуля» (связный список, хеш-таблица, двоичное дерево поиска), применить их для хранения записей телефонного справочника и экспериментально сравнить производительность основных операций. + +## Параметры эксперимента + +- Количество записей: 10000 +- Количество повторов каждого теста: 5 +- Размер хеш-таблицы: 1000 корзин + +## Результаты экспериментов + +### 1. Связный список + +| Режим | Вставка (сек) | Поиск (сек) | Удаление (сек) | +|-------|---------------|-------------|----------------| +| Случайный | {ll_random_insert:.4f} | {ll_random_find:.4f} | {ll_random_delete:.4f} | +| Отсортированный | {ll_sorted_insert:.4f} | {ll_sorted_find:.4f} | {ll_sorted_delete:.4f} | + +### 2. Хеш-таблица + +| Режим | Вставка (сек) | Поиск (сек) | Удаление (сек) | +|-------|---------------|-------------|----------------| +| Случайный | {ht_random_insert:.4f} | {ht_random_find:.4f} | {ht_random_delete:.4f} | +| Отсортированный | {ht_sorted_insert:.4f} | {ht_sorted_find:.4f} | {ht_sorted_delete:.4f} | + +### 3. Двоичное дерево поиска (BST) + +| Режим | Вставка (сек) | Поиск (сек) | Удаление (сек) | +|-------|---------------|-------------|----------------| +| Случайный | {bst_random_insert:.4f} | {bst_random_find:.4f} | {bst_random_delete:.4f} | +| Отсортированный | {bst_sorted_insert:.4f} | {bst_sorted_find:.4f} | {bst_sorted_delete:.4f} | + +## Анализ результатов + +### 1. Влияние порядка данных на BST +При добавлении уже отсортированных элементов BST вырождается в линейную структуру — сложность падает с O(log n) до O(n). +Время вставки выросло с {bst_random_insert:.4f} до {bst_sorted_insert:.4f} секунд — замедление в {bst_sorted_insert/bst_random_insert:.1f} раза. + +### 2. Почему хеш-таблица не чувствительна к порядку + +Хеш-функция равномерно распределяет ключи по корзинам независимо от их исходного порядка. Поэтому последовательность добавления практически не влияет на производительность. +Сравнение случайного и упорядоченного ввода: +- Случайный режим: {ht_random_insert:.4f} с +- Упорядоченный режим: {ht_sorted_insert:.4f} с +- Различие: {ht_sorted_insert/ht_random_insert:.2f} + +### 3. Почему связный список медленный при поиске + +Поиск в связном списке требует линейного обхода O(n) — структура не поддерживает произвольный доступ. Это делает его непригодным для крупных справочников, где нужен быстрый поиск по ключу. + +Сравнение скорости поиска на случайных данных: +- LinkedList: {ll_random_find:.4f} сек +- HashTable: {ht_random_find:.4f} сек (преимущество в {ll_random_find/ht_random_find:.1f}) +- BST: {bst_random_find:.4f} сек + +### 4. Сравнение удаления + +| Структура | Сложность | Время на 50 удалений (случайные данные) | +|-----------|-----------|------------------------------------------| +| Связный список | O(n) | {ll_random_delete:.4f} сек| +| Хеш-таблица | O(1) в среднем | {ht_random_delete:.4f} сек | +| BST | O(log n) в среднем | {bst_random_delete:.4f} сек | + +## Вывод: + +| Задача | Рекомендация | Почему | +|--------|-------------|--------| +| Частый поиск | Хеш-таблица | O(1) в среднем, не зависит от порядка | +| Частые вставки/удаления | Хеш-таблица | Амортизированное O(1) | +| Нужен отсортированный вывод | Сбалансированное дерево (AVL/Red-Black) | In-order обход даёт сортировку | +| Мало данных (<100 элементов) | Связный список или массив | Простота, накладные расходы не оправданы | +| Последовательный доступ (очередь/стек) | Связный список | Вставка/удаление в начало/конец за O(1) | + +## Заключение +Проведённый эксперимент подтверждает теоретические оценки сложности: + +1. **Небалансированное BST это плохой выбор** при работе с реальными данными, которые могут оказаться упорядоченными. Деградация до O(n) делает его непригодным для надёжных систем. + +2. **Хеш-таблица показывает стабильные результаты** вне зависимости от порядка входных данных — ключевое преимущество для телефонного справочника с произвольными именами абонентов. + +3. **Связный список — нишевый инструмент**, эффективный только при работе с малыми объёмами данных. + +""" + + with open(filename, 'w', encoding='utf-8') as f: + f.write(report_content) + +def print_analysis(results): + print("\n" + "="*60) + print("Анализ результатов") + print("="*60) + + best_insert = min(results, key=lambda x: x['insert_mean']) + best_find = min(results, key=lambda x: x['find_mean']) + best_delete = min(results, key=lambda x: x['delete_mean']) + + print(f"\n Лучшая для вставки: {best_insert['structure']} ({best_insert['mode']}) - {best_insert['insert_mean']:.4f} сек") + print(f" Лучшая для поиска: {best_find['structure']} ({best_find['mode']}) - {best_find['find_mean']:.4f} сек") + print(f" Лучшая для удаления: {best_delete['structure']} ({best_delete['mode']}) - {best_delete['delete_mean']:.4f} сек") + + bst_random = None + bst_sorted = None + for res in results: + if res['structure'] == 'bst' and res['mode'] == 'случайный': + bst_random = res + elif res['structure'] == 'bst' and res['mode'] == 'отсортированный': + bst_sorted = res + + if bst_random and bst_sorted: + print("\n Влияние порядка данных на BST:") + print(f" Вставка: случайный {bst_random['insert_mean']:.4f} сек vs отсортированный {bst_sorted['insert_mean']:.4f} сек") + print(f" Деградация в {bst_sorted['insert_mean']/bst_random['insert_mean']:.1f}x") + + ht_random = None + ht_sorted = None + for res in results: + if res['structure'] == 'hashtable' and res['mode'] == 'случайный': + ht_random = res + elif res['structure'] == 'hashtable' and res['mode'] == 'отсортированный': + ht_sorted = res + + if ht_random and ht_sorted: + print("\n Чувствительность хеш-таблицы к порядку:") + print(f" Вставка: случайный {ht_random['insert_mean']:.4f} сек vs отсортированный {ht_sorted['insert_mean']:.4f} сек") + print(f" Отношение: {ht_sorted['insert_mean']/ht_random['insert_mean']:.2f}x (почти не чувствительна)") + + ll_random = None + for res in results: + if res['structure'] == 'linkedlist' and res['mode'] == 'случайный': + ll_random = res + elif res['structure'] == 'hashtable' and res['mode'] == 'случайный': + ht_random = res + + if ll_random and ht_random: + print("\n Сравнение скорости поиска:") + print(f" LinkedList: {ll_random['find_mean']:.4f} сек") + print(f" HashTable: {ht_random['find_mean']:.4f} сек") + print(f" HashTable быстрее в {ll_random['find_mean']/ht_random['find_mean']:.1f} раз") \ No newline at end of file diff --git a/ZelentsovAV/task2/builders.py b/ZelentsovAV/task2/builders.py new file mode 100644 index 0000000..6837933 --- /dev/null +++ b/ZelentsovAV/task2/builders.py @@ -0,0 +1,56 @@ +from abc import ABC, abstractmethod +from models import Cell, Maze + + +class MazeBuilder(ABC): + + @abstractmethod + def build_from_file(self, filename: str) -> Maze: + pass + + +class TextFileMazeBuilder(MazeBuilder): + + WALL_CHAR = '#' + START_CHAR = 'S' + EXIT_CHAR = 'E' + PASS_CHAR = ' ' + + def build_from_file(self, filename: str) -> Maze: + with open(filename, 'r', encoding='utf-8') as f: + lines = [line.rstrip('\n') for line in f.readlines()] + + if not lines: + raise ValueError("Файл с лабиринтом пуст") + + height = len(lines) + width = max(len(line) for line in lines) + + maze = Maze(width, height) + + for y, line in enumerate(lines): + for x, ch in enumerate(line): + if x >= width: + continue + + cell = Cell(x, y) + + if ch == self.WALL_CHAR: + cell.is_wall = True + elif ch == self.START_CHAR: + cell.is_start = True + elif ch == self.EXIT_CHAR: + cell.is_exit = True + elif ch == self.PASS_CHAR: + pass + else: + cell.is_wall = True + + maze.set_cell(x, y, cell) + + if maze.start is None: + raise ValueError("В лабиринте нет стартовой клетки (S)") + if maze.exit is None: + raise ValueError("В лабиринте нет выхода (E)") + + return maze \ No newline at end of file diff --git a/ZelentsovAV/task2/commands.py b/ZelentsovAV/task2/commands.py new file mode 100644 index 0000000..4abbc4a --- /dev/null +++ b/ZelentsovAV/task2/commands.py @@ -0,0 +1,62 @@ +from abc import ABC, abstractmethod +from typing import Optional +from models import Cell, Maze + + +class Player: + + def __init__(self, start_cell: Cell): + self.current_cell = start_cell + + def move_to(self, new_cell: Cell) -> None: + self.current_cell = new_cell + + +class Command(ABC): + + @abstractmethod + def execute(self) -> bool: + pass + + @abstractmethod + def undo(self) -> None: + pass + + +class MoveCommand(Command): + + def __init__(self, player: Player, maze: Maze, direction: str): + self.player = player + self.maze = maze + self.direction = direction + self.previous_cell: Optional[Cell] = None + self.new_cell: Optional[Cell] = None + + def _get_target_cell(self) -> Optional[Cell]: + x, y = self.player.current_cell.x, self.player.current_cell.y + + if self.direction == 'w': + y -= 1 + elif self.direction == 's': + y += 1 + elif self.direction == 'a': + x -= 1 + elif self.direction == 'd': + x += 1 + else: + return None + + return self.maze.get_cell(x, y) + + def execute(self) -> bool: + self.previous_cell = self.player.current_cell + self.new_cell = self._get_target_cell() + + if self.new_cell and self.new_cell.is_passable(): + self.player.move_to(self.new_cell) + return True + return False + + def undo(self) -> None: + if self.previous_cell: + self.player.move_to(self.previous_cell) \ No newline at end of file diff --git a/ZelentsovAV/task2/docs/otchetlaba2.docx b/ZelentsovAV/task2/docs/otchetlaba2.docx new file mode 100644 index 0000000..46acd26 Binary files /dev/null and b/ZelentsovAV/task2/docs/otchetlaba2.docx differ diff --git a/ZelentsovAV/task2/experiment_results.csv b/ZelentsovAV/task2/experiment_results.csv new file mode 100644 index 0000000..f55958b --- /dev/null +++ b/ZelentsovAV/task2/experiment_results.csv @@ -0,0 +1,13 @@ +maze_file,maze_size,strategy,time_mean,time_min,time_max,visited_mean,path_length_mean,path_found +small.txt,10×10,BFS,0.13488009572029114,0.10789930820465088,0.22369995713233948,15.0,15.0,True +small.txt,10×10,DFS,0.06621982902288437,0.05200039595365524,0.11539924889802933,21.0,21.0,True +small.txt,10×10,A*,0.1621600240468979,0.11659972369670868,0.21409988403320312,15.0,15.0,True +medium.txt,20×11,BFS,0.8280398324131966,0.6230995059013367,1.116500236093998,26.0,26.0,True +medium.txt,20×11,DFS,0.9217998012900352,0.771399587392807,1.2620994821190834,90.0,90.0,True +medium.txt,20×11,A*,1.2338800355792046,1.066099852323532,1.5382999554276466,26.0,26.0,True +large.txt,30×15,BFS,1.9566401839256287,1.3727005571126938,2.646399661898613,40.0,40.0,True +large.txt,30×15,DFS,1.7152601853013039,1.3266997411847115,2.037300728261471,196.0,196.0,True +large.txt,30×15,A*,1.906839944422245,1.2140991166234016,2.70990002900362,40.0,40.0,True +empty.txt,30×1,BFS,0.09321998804807663,0.07409974932670593,0.12030079960823059,30.0,30.0,True +empty.txt,30×1,DFS,0.24830028414726257,0.21299999207258224,0.2831006422638893,30.0,30.0,True +empty.txt,30×1,A*,0.17731990665197372,0.09519979357719421,0.30350033193826675,30.0,30.0,True diff --git a/ZelentsovAV/task2/experiments.py b/ZelentsovAV/task2/experiments.py new file mode 100644 index 0000000..018a9a9 --- /dev/null +++ b/ZelentsovAV/task2/experiments.py @@ -0,0 +1,94 @@ +import csv +import time +from typing import List, Dict +from models import Maze +from builders import TextFileMazeBuilder +from strategies import BFSStrategy, DFSStrategy, AStarStrategy +from solver import MazeSolver + + +def run_experiment(maze: Maze, strategy_name: str, strategy, repeats: int = 5) -> Dict: + times = [] + visited_counts = [] + path_lengths = [] + path_found = True + + for _ in range(repeats): + solver = MazeSolver(maze, strategy) + path, stats = solver.solve() + + times.append(stats.time_ms) + visited_counts.append(stats.visited_cells) + path_lengths.append(stats.path_length) + path_found = stats.path_found + + return { + 'strategy': strategy_name, + 'time_mean': sum(times) / len(times), + 'time_min': min(times), + 'time_max': max(times), + 'visited_mean': sum(visited_counts) / len(visited_counts), + 'path_length_mean': sum(path_lengths) / len(path_lengths) if path_found else 0, + 'path_found': path_found + } + + +def run_all_experiments(maze_files: List[str], repeats: int = 5) -> List[Dict]: + builder = TextFileMazeBuilder() + strategies = [ + ('BFS', BFSStrategy()), + ('DFS', DFSStrategy()), + ('A*', AStarStrategy()) + ] + + results = [] + + for maze_file in maze_files: + try: + maze = builder.build_from_file(maze_file) + except (ValueError, FileNotFoundError) as e: + print(f" Ошибка: {e}") + continue + + print(f" Размер: {maze.width}×{maze.height}") + print(f" Старт: ({maze.start.x}, {maze.start.y})") + print(f" Выход: ({maze.exit.x}, {maze.exit.y})") + + for strategy_name, strategy in strategies: + print(f" Тестирование: {strategy_name}") + result = run_experiment(maze, strategy_name, strategy, repeats) + result['maze_file'] = maze_file.split('/')[-1] + result['maze_size'] = f"{maze.width}×{maze.height}" + results.append(result) + + status = "ok" if result['path_found'] else "ne ok" + print(f" {status} Время: {result['time_mean']:.2f} мс, " + f"Посещено: {result['visited_mean']:.0f}, " + f"Путь: {result['path_length_mean']:.0f}") + + return results + + +def save_results_to_csv(results: List[Dict], filename: str = "experiment_results.csv") -> None: + with open(filename, 'w', newline='', encoding='utf-8') as f: + writer = csv.DictWriter(f, fieldnames=[ + 'maze_file', 'maze_size', 'strategy', + 'time_mean', 'time_min', 'time_max', + 'visited_mean', 'path_length_mean', 'path_found' + ]) + writer.writeheader() + writer.writerows(results) + + + +def print_results_table(results: List[Dict]) -> None: + print("\n" + "=" * 80) + print("РЕЗУЛЬТАТЫ ЭКСПЕРИМЕНТОВ") + print("=" * 80) + + for res in results: + print(f"\nЛабиринт: {res['maze_file']}") + print(f" Стратегия: {res['strategy']}") + print(f" Время (ср): {res['time_mean']:.2f} мс") + print(f" Посещено: {res['visited_mean']:.0f} клеток") + print(f" Длина пути: {res['path_length_mean']:.0f}") \ No newline at end of file diff --git a/ZelentsovAV/task2/main.py b/ZelentsovAV/task2/main.py new file mode 100644 index 0000000..6926482 --- /dev/null +++ b/ZelentsovAV/task2/main.py @@ -0,0 +1,146 @@ +import os +from builders import TextFileMazeBuilder +from strategies import BFSStrategy, DFSStrategy, AStarStrategy +from solver import MazeSolver +from observers import ConsoleView +from commands import Player +from experiments import run_all_experiments, save_results_to_csv, print_results_table + + +def create_test_mazes(): + os.makedirs("mazes", exist_ok=True) + + small = """########## +#S # +# ### ## # +# # # +### # #### +# # # +# ### # # +# # # +# # E# +##########""" + + medium = """#################### +#S # +# # # # # # # # # # +# # +# # # # # # # # # # +# # +# # # # # # # # # # +# # +# # # # # # # # # # +# E# +####################""" + + large = """############################## +#S # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# E# +##############################""" + + empty = "S" + " " * 28 + "E" + + no_exit = """####### +#S # +# ### # +# # # +#######""" + + with open("mazes/small.txt", "w") as f: + f.write(small) + with open("mazes/medium.txt", "w") as f: + f.write(medium) + with open("mazes/large.txt", "w") as f: + f.write(large) + with open("mazes/empty.txt", "w") as f: + f.write(empty) + with open("mazes/no_exit.txt", "w") as f: + f.write(no_exit) + + + +def demo_maze_solver(): + print("\n" + "=" * 60) + print("ДЕМОНСТРАЦИЯ РАБОТЫ MAZE SOLVER") + print("=" * 60) + + builder = TextFileMazeBuilder() + view = ConsoleView() + + maze = builder.build_from_file("mazes/small.txt") + view.update("maze_loaded", {"maze": maze}) + + strategies = [ + ("BFS", BFSStrategy(), "BFS"), + ("DFS", DFSStrategy(), "DFSs"), + ("A*", AStarStrategy(), "A*") + ] + + for name, strategy, description in strategies: + solver = MazeSolver(maze, strategy) + view.update("search_start", {"algorithm": description}) + + path, stats = solver.solve() + + if stats.path_found: + view.update("path_found", {"maze": maze, "path": path, "stats": stats}) + else: + view.update("no_path", {"stats": stats}) + + +def demo_player_controls(): + print("\n" + "=" * 60) + print("Command + Observer") + print("=" * 60) + + builder = TextFileMazeBuilder() + view = ConsoleView() + maze = builder.build_from_file("mazes/small.txt") + + player = Player(maze.start) + + view.update("maze_loaded", {"maze": maze}) + view.render(maze, player_position=player.current_cell) + + +def run_experiments(): + print("\n" + "=" * 60) + print("ЭКСПЕРИМЕНТАЛЬНОЕ СРАВНЕНИЕ АЛГОРИТМОВ") + print("=" * 60) + + maze_files = [ + "mazes/small.txt", + "mazes/medium.txt", + "mazes/large.txt", + "mazes/empty.txt", + "mazes/no_exit.txt" + ] + + results = run_all_experiments(maze_files, repeats=5) + save_results_to_csv(results) + print_results_table(results) + + +def main(): + print("Объектно-ориентированная реализация с паттернами") + print("Паттерны: Builder, Strategy, Observer, Command") + + create_test_mazes() + demo_maze_solver() + demo_player_controls() + run_experiments() + + +if __name__ == "__main__": + main() \ No newline at end of file diff --git a/ZelentsovAV/task2/mazes/empty.txt b/ZelentsovAV/task2/mazes/empty.txt new file mode 100644 index 0000000..172bb4f --- /dev/null +++ b/ZelentsovAV/task2/mazes/empty.txt @@ -0,0 +1 @@ +S E \ No newline at end of file diff --git a/ZelentsovAV/task2/mazes/large.txt b/ZelentsovAV/task2/mazes/large.txt new file mode 100644 index 0000000..143173c --- /dev/null +++ b/ZelentsovAV/task2/mazes/large.txt @@ -0,0 +1,15 @@ +############################## +#S # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# # +# # # # # # # # # # # # # # # +# E# +############################## \ No newline at end of file diff --git a/ZelentsovAV/task2/mazes/medium.txt b/ZelentsovAV/task2/mazes/medium.txt new file mode 100644 index 0000000..e52ac72 --- /dev/null +++ b/ZelentsovAV/task2/mazes/medium.txt @@ -0,0 +1,11 @@ +#################### +#S # +# # # # # # # # # # +# # +# # # # # # # # # # +# # +# # # # # # # # # # +# # +# # # # # # # # # # +# E# +#################### \ No newline at end of file diff --git a/ZelentsovAV/task2/mazes/no_exit.txt b/ZelentsovAV/task2/mazes/no_exit.txt new file mode 100644 index 0000000..c9a85c0 --- /dev/null +++ b/ZelentsovAV/task2/mazes/no_exit.txt @@ -0,0 +1,5 @@ +####### +#S # +# ### # +# # # +####### \ No newline at end of file diff --git a/ZelentsovAV/task2/mazes/small.txt b/ZelentsovAV/task2/mazes/small.txt new file mode 100644 index 0000000..9cbc84e --- /dev/null +++ b/ZelentsovAV/task2/mazes/small.txt @@ -0,0 +1,10 @@ +########## +#S # +# ### ## # +# # # +### # #### +# # # +# ### # # +# # # +# # E# +########## \ No newline at end of file diff --git a/ZelentsovAV/task2/models.py b/ZelentsovAV/task2/models.py new file mode 100644 index 0000000..5932d5f --- /dev/null +++ b/ZelentsovAV/task2/models.py @@ -0,0 +1,79 @@ +from typing import List, Optional + + +class Cell: + + def __init__(self, x: int, y: int): + self.x = x + self.y = y + self.is_wall = False + self.is_start = False + self.is_exit = False + + def is_passable(self) -> bool: + return not self.is_wall + + def __eq__(self, other) -> bool: + if not isinstance(other, Cell): + return False + return self.x == other.x and self.y == other.y + + def __hash__(self): + return hash((self.x, self.y)) + + def __repr__(self): + return f"Cell({self.x}, {self.y})" + + +class Maze: + + def __init__(self, width: int, height: int): + self.width = width + self.height = height + self._cells: List[List[Optional[Cell]]] = [[None for _ in range(width)] for _ in range(height)] + self.start: Optional[Cell] = None + self.exit: Optional[Cell] = None + + def set_cell(self, x: int, y: int, cell: Cell) -> None: + if 0 <= x < self.width and 0 <= y < self.height: + self._cells[y][x] = cell + if cell.is_start: + self.start = cell + if cell.is_exit: + self.exit = cell + + def get_cell(self, x: int, y: int) -> Optional[Cell]: + if 0 <= x < self.width and 0 <= y < self.height: + return self._cells[y][x] + return None + + def get_neighbors(self, cell: Cell) -> List[Cell]: + neighbors = [] + directions = [(0, -1), (0, 1), (-1, 0), (1, 0)] + + for dx, dy in directions: + nx, ny = cell.x + dx, cell.y + dy + neighbor = self.get_cell(nx, ny) + if neighbor and neighbor.is_passable(): + neighbors.append(neighbor) + + return neighbors + + def __str__(self) -> str: + result = [] + for y in range(self.height): + row = [] + for x in range(self.width): + cell = self.get_cell(x, y) + if cell is None: + row.append('?') + elif cell.is_start: + row.append('S') + elif cell.is_exit: + row.append('E') + elif cell.is_wall: + row.append('#') + else: + row.append(' ') + result.append(''.join(row)) + return '\n'.join(result) \ No newline at end of file diff --git a/ZelentsovAV/task2/observers.py b/ZelentsovAV/task2/observers.py new file mode 100644 index 0000000..eb10114 --- /dev/null +++ b/ZelentsovAV/task2/observers.py @@ -0,0 +1,66 @@ +from abc import ABC, abstractmethod +from typing import List, Optional +from models import Cell, Maze + + +class Observer(ABC): + + @abstractmethod + def update(self, event: str, data: dict) -> None: + pass + + +class ConsoleView(Observer): + + def render(self, maze: Maze, player_position: Optional[Cell] = None, path: Optional[List[Cell]] = None) -> None: + path_set = set(path) if path else set() + + print("\n+" + "-" * maze.width + "+") + + for y in range(maze.height): + row = [] + for x in range(maze.width): + cell = maze.get_cell(x, y) + if cell is None: + row.append('?') + elif player_position and cell == player_position: + row.append('@') + elif cell.is_start: + row.append('S') + elif cell.is_exit: + row.append('E') + elif cell in path_set: + row.append('*') + elif cell.is_wall: + row.append('#') + else: + row.append(' ') + print("|" + ''.join(row) + "|") + + print("+" + "-" * maze.width + "+") + + def update(self, event: str, data: dict) -> None: + if event == "maze_loaded": + maze = data.get('maze') + print("\n Лабиринт загружен:") + self.render(maze) + + elif event == "search_start": + algorithm = data.get('algorithm', 'Unknown') + print(f"\n Начинаем поиск алгоритмом: {algorithm}") + + elif event == "path_found": + maze = data.get('maze') + path = data.get('path') + stats = data.get('stats') + self.render(maze, path=path) + + elif event == "no_path": + stats = data.get('stats') + print(f"\n {stats}") + + elif event == "player_moved": + maze = data.get('maze') + player = data.get('player') + if player: + self.render(maze, player_position=player.current_cell) \ No newline at end of file diff --git a/ZelentsovAV/task2/solver.py b/ZelentsovAV/task2/solver.py new file mode 100644 index 0000000..137e481 --- /dev/null +++ b/ZelentsovAV/task2/solver.py @@ -0,0 +1,49 @@ +import time +from dataclasses import dataclass +from typing import List, Optional, Tuple +from models import Cell, Maze +from strategies import PathFindingStrategy + + +@dataclass +class SearchStats: + time_ms: float + visited_cells: int + path_length: int + path_found: bool = True + + def __str__(self) -> str: + if not self.path_found: + return f"Путь не найден (время: {self.time_ms:.2f} мс)" + return (f"Время: {self.time_ms:.2f} мс, " + f"Посещено клеток: {self.visited_cells}, " + f"Длина пути: {self.path_length}") + + +class MazeSolver: + + def __init__(self, maze: Maze, strategy: Optional[PathFindingStrategy] = None): + self.maze = maze + self._strategy = strategy + + def set_strategy(self, strategy: PathFindingStrategy) -> None: + self._strategy = strategy + + def solve(self) -> Tuple[List[Cell], SearchStats]: + if self._strategy is None: + raise ValueError("Стратегия не установлена") + + start_time = time.perf_counter() + path = self._strategy.find_path(self.maze, self.maze.start, self.maze.exit) + end_time = time.perf_counter() + + time_ms = (end_time - start_time) * 1000 + + stats = SearchStats( + time_ms=time_ms, + visited_cells=len(path) if path else 0, + path_length=len(path) if path else 0, + path_found=bool(path) + ) + + return path, stats \ No newline at end of file diff --git a/ZelentsovAV/task2/strategies.py b/ZelentsovAV/task2/strategies.py new file mode 100644 index 0000000..ba797ae --- /dev/null +++ b/ZelentsovAV/task2/strategies.py @@ -0,0 +1,99 @@ +from abc import ABC, abstractmethod +from collections import deque +from heapq import heappush, heappop +from typing import List, Dict, Optional +from models import Cell, Maze + + +class PathFindingStrategy(ABC): + + @abstractmethod + def find_path(self, maze: Maze, start: Cell, exit_cell: Cell) -> List[Cell]: + pass + + +class BFSStrategy(PathFindingStrategy): + + def find_path(self, maze: Maze, start: Cell, exit_cell: Cell) -> List[Cell]: + queue = deque([start]) + visited = {start} + parent: Dict[Cell, Optional[Cell]] = {start: None} + + while queue: + current = queue.popleft() + + if current == exit_cell: + return self._reconstruct_path(parent, current) + + for neighbor in maze.get_neighbors(current): + if neighbor not in visited: + visited.add(neighbor) + parent[neighbor] = current + queue.append(neighbor) + + return [] + + def _reconstruct_path(self, parent: Dict[Cell, Optional[Cell]], current: Cell) -> List[Cell]: + path = [] + while current is not None: + path.append(current) + current = parent.get(current) + return list(reversed(path)) + + +class DFSStrategy(PathFindingStrategy): + + def find_path(self, maze: Maze, start: Cell, exit_cell: Cell) -> List[Cell]: + stack = [(start, [start])] + visited = {start} + + while stack: + current, path = stack.pop() + + if current == exit_cell: + return path + + for neighbor in maze.get_neighbors(current): + if neighbor not in visited: + visited.add(neighbor) + stack.append((neighbor, path + [neighbor])) + + return [] + + +class AStarStrategy(PathFindingStrategy): + + def _heuristic(self, cell: Cell, exit_cell: Cell) -> int: + return abs(cell.x - exit_cell.x) + abs(cell.y - exit_cell.y) + + def find_path(self, maze: Maze, start: Cell, exit_cell: Cell) -> List[Cell]: + counter = 0 + open_set = [(self._heuristic(start, exit_cell), counter, start)] + + g_score: Dict[Cell, float] = {start: 0} + parent: Dict[Cell, Optional[Cell]] = {start: None} + + while open_set: + _, _, current = heappop(open_set) + + if current == exit_cell: + return self._reconstruct_path(parent, current) + + for neighbor in maze.get_neighbors(current): + tentative_g = g_score[current] + 1 + + if neighbor not in g_score or tentative_g < g_score[neighbor]: + parent[neighbor] = current + g_score[neighbor] = tentative_g + counter += 1 + f = tentative_g + self._heuristic(neighbor, exit_cell) + heappush(open_set, (f, counter, neighbor)) + + return [] + + def _reconstruct_path(self, parent: Dict[Cell, Optional[Cell]], current: Cell) -> List[Cell]: + path = [] + while current is not None: + path.append(current) + current = parent.get(current) + return list(reversed(path)) \ No newline at end of file diff --git a/ZelentsovAV/task2/visualize.py b/ZelentsovAV/task2/visualize.py new file mode 100644 index 0000000..70117f6 --- /dev/null +++ b/ZelentsovAV/task2/visualize.py @@ -0,0 +1,77 @@ +import pandas as pd +import matplotlib.pyplot as plt +import numpy as np +from pathlib import Path + + +def plot_results(csv_file='experiment_results.csv'): + + if not Path(csv_file).exists(): + print(f"❌ {csv_file} не найден. Сначала запустите main.py") + return + + df = pd.read_csv(csv_file) + + df = df[df['path_found'] == True] + + if df.empty: + print("Нет данных для графиков") + return + + mazes = [m.replace('.txt', '') for m in df['maze_file'].unique()] + strategies = df['strategy'].unique() + + fig, axes = plt.subplots(1, 3, figsize=(14, 5)) + fig.suptitle('Сравнение алгоритмов поиска в лабиринте', fontsize=14, fontweight='bold') + + x = np.arange(len(mazes)) + width = 0.25 + colors = {'BFS': '#3498db', 'DFS': '#2ecc71', 'A*': '#e74c3c'} + + for i, strategy in enumerate(strategies): + times, visited, lengths = [], [], [] + + for maze in df['maze_file'].unique(): + data = df[(df['strategy'] == strategy) & (df['maze_file'] == maze)] + if not data.empty: + times.append(data['time_mean'].values[0]) + visited.append(data['visited_mean'].values[0]) + lengths.append(data['path_length_mean'].values[0]) + else: + times.append(0) + visited.append(0) + lengths.append(0) + + axes[0].bar(x + i*width, times, width, label=strategy, + color=colors.get(strategy, 'gray'), alpha=0.7) + axes[1].bar(x + i*width, visited, width, label=strategy, + color=colors.get(strategy, 'gray'), alpha=0.7) + axes[2].bar(x + i*width, lengths, width, label=strategy, + color=colors.get(strategy, 'gray'), alpha=0.7) + + axes[0].set_title(' Время выполнения (мс)') + axes[0].set_xticks(x + width) + axes[0].set_xticklabels(mazes, rotation=45, ha='right') + axes[0].legend() + axes[0].grid(True, alpha=0.3) + + axes[1].set_title(' Посещённые клетки') + axes[1].set_xticks(x + width) + axes[1].set_xticklabels(mazes, rotation=45, ha='right') + axes[1].legend() + axes[1].grid(True, alpha=0.3) + + axes[2].set_title(' Длина пути') + axes[2].set_xticks(x + width) + axes[2].set_xticklabels(mazes, rotation=45, ha='right') + axes[2].legend() + axes[2].grid(True, alpha=0.3) + + plt.tight_layout() + plt.savefig('experiment_results.png', dpi=150, bbox_inches='tight') + plt.show() + + + +if __name__ == "__main__": + plot_results() \ No newline at end of file