diff --git a/SmirnovVS/428.md b/SmirnovVS/428.md
new file mode 100644
index 0000000..fb8a210
--- /dev/null
+++ b/SmirnovVS/428.md
@@ -0,0 +1 @@
+428
\ No newline at end of file
diff --git a/SmirnovVS/docs/data/1-st-exercize/experiment.py b/SmirnovVS/docs/data/1-st-exercize/experiment.py
new file mode 100644
index 0000000..63e0879
--- /dev/null
+++ b/SmirnovVS/docs/data/1-st-exercize/experiment.py
@@ -0,0 +1,132 @@
+"""Экспериментальное сравнение структур данных."""
+
+import argparse
+import csv
+import random
+from pathlib import Path
+from statistics import mean
+from time import perf_counter
+
+from phonebook import (
+    bst_delete, bst_find, bst_insert,
+    ht_delete, ht_find, ht_insert,
+    ll_delete, ll_find, ll_insert,
+)
+
+
+def generate_records(size):
+    return [(f"User_{index:05d}", f"+7{index:010d}") for index in range(size)]
+
+
+def measure_once(structure, records, existing_names, missing_names, deleted_names, bucket_count):
+    started = perf_counter()
+    if structure == "LinkedList":
+        data = None
+        for name, phone in records:
+            data = ll_insert(data, name, phone)
+        insert_time = perf_counter() - started
+
+        started = perf_counter()
+        for name in existing_names + missing_names:
+            ll_find(data, name)
+        find_time = perf_counter() - started
+
+        started = perf_counter()
+        for name in deleted_names:
+            data = ll_delete(data, name)
+        delete_time = perf_counter() - started
+    elif structure == "HashTable":
+        data = [None] * bucket_count
+        for name, phone in records:
+            ht_insert(data, name, phone)
+        insert_time = perf_counter() - started
+
+        started = perf_counter()
+        for name in existing_names + missing_names:
+            ht_find(data, name)
+        find_time = perf_counter() - started
+
+        started = perf_counter()
+        for name in deleted_names:
+            ht_delete(data, name)
+        delete_time = perf_counter() - started
+    else:
+        data = None
+        for name, phone in records:
+            data = bst_insert(data, name, phone)
+        insert_time = perf_counter() - started
+
+        started = perf_counter()
+        for name in existing_names + missing_names:
+            bst_find(data, name)
+        find_time = perf_counter() - started
+
+        started = perf_counter()
+        for name in deleted_names:
+            data = bst_delete(data, name)
+        delete_time = perf_counter() - started
+
+    return {"insert": insert_time, "find_110": find_time, "delete_50": delete_time}
+
+
+def run_experiment(size=3000, repeats=5, seed=2026, output_dir="docs/data"):
+    rng = random.Random(seed)
+    sorted_records = generate_records(size)
+    shuffled_records = sorted_records.copy()
+    rng.shuffle(shuffled_records)
+    modes = {"shuffled": shuffled_records, "sorted": sorted_records}
+    rows = []
+
+    for mode, records in modes.items():
+        names = [record[0] for record in records]
+        test_cases = []
+        for run in range(1, repeats + 1):
+            test_cases.append((
+                run,
+                rng.sample(names, min(100, size)),
+                [f"None_{index}" for index in range(10)],
+                rng.sample(names, min(50, size)),
+            ))
+        for structure in ("LinkedList", "HashTable", "BST"):
+            for run, existing, missing, deleted in test_cases:
+                timings = measure_once(structure, records, existing, missing, deleted, max(17, size * 2 + 1))
+                for operation, elapsed in timings.items():
+                    rows.append({
+                        "structure": structure,
+                        "mode": mode,
+                        "operation": operation,
+                        "run": run,
+                        "time_seconds": elapsed,
+                    })
+
+    output = Path(output_dir)
+    output.mkdir(parents=True, exist_ok=True)
+    raw_path = output / "results_raw.csv"
+    with raw_path.open("w", newline="", encoding="utf-8-sig") as file:
+        writer = csv.DictWriter(file, fieldnames=rows[0].keys())
+        writer.writeheader()
+        writer.writerows(rows)
+
+    groups = {}
+    for row in rows:
+        key = (row["structure"], row["mode"], row["operation"])
+        groups.setdefault(key, []).append(row["time_seconds"])
+    summary = [
+        {"structure": key[0], "mode": key[1], "operation": key[2], "mean_seconds": mean(values)}
+        for key, values in groups.items()
+    ]
+    summary_path = output / "results_summary.csv"
+    with summary_path.open("w", newline="", encoding="utf-8-sig") as file:
+        writer = csv.DictWriter(file, fieldnames=summary[0].keys())
+        writer.writeheader()
+        writer.writerows(summary)
+    return raw_path, summary_path
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Сравнение структур телефонного справочника")
+    parser.add_argument("--size", type=int, default=3000)
+    parser.add_argument("--repeats", type=int, default=5)
+    args = parser.parse_args()
+    raw, summary = run_experiment(args.size, args.repeats)
+    print(f"Полные замеры: {raw}\nСредние значения: {summary}")
diff --git a/SmirnovVS/docs/data/1-st-exercize/main.py b/SmirnovVS/docs/data/1-st-exercize/main.py
new file mode 100644
index 0000000..0bf21c6
--- /dev/null
+++ b/SmirnovVS/docs/data/1-st-exercize/main.py
@@ -0,0 +1,25 @@
+from phonebook import ht_delete, ht_find, ht_insert, ht_list_all
+
+
+def main():
+    phonebook = [None] * 101
+    print("Телефонный справочник. Команды: add, find, delete, list, exit")
+    while True:
+        command = input("> ").strip().lower()
+        if command == "add":
+            ht_insert(phonebook, input("Имя: ").strip(), input("Телефон: ").strip())
+        elif command == "find":
+            print(ht_find(phonebook, input("Имя: ").strip()) or "Запись не найдена")
+        elif command == "delete":
+            ht_delete(phonebook, input("Имя: ").strip())
+        elif command == "list":
+            for name, phone in ht_list_all(phonebook):
+                print(f"{name}: {phone}")
+        elif command == "exit":
+            break
+        else:
+            print("Неизвестная команда")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/SmirnovVS/docs/data/1-st-exercize/phonebook.py b/SmirnovVS/docs/data/1-st-exercize/phonebook.py
new file mode 100644
index 0000000..5c3ec08
--- /dev/null
+++ b/SmirnovVS/docs/data/1-st-exercize/phonebook.py
@@ -0,0 +1,162 @@
+"""Телефонный справочник на трёх структурах данных."""
+
+
+def _node(name, phone, next_node=None):
+    return {"name": name, "phone": phone, "next": next_node}
+
+
+def ll_insert(head, name, phone):
+    """Добавить запись в конец списка или обновить существующую."""
+    if head is None:
+        return _node(name, phone)
+
+    current = head
+    while True:
+        if current["name"] == name:
+            current["phone"] = phone
+            return head
+        if current["next"] is None:
+            current["next"] = _node(name, phone)
+            return head
+        current = current["next"]
+
+
+def ll_find(head, name):
+    current = head
+    while current is not None:
+        if current["name"] == name:
+            return current["phone"]
+        current = current["next"]
+    return None
+
+
+def ll_delete(head, name):
+    if head is None:
+        return None
+    if head["name"] == name:
+        return head["next"]
+
+    previous, current = head, head["next"]
+    while current is not None:
+        if current["name"] == name:
+            previous["next"] = current["next"]
+            break
+        previous, current = current, current["next"]
+    return head
+
+
+def ll_list_all(head):
+    records = []
+    current = head
+    while current is not None:
+        records.append((current["name"], current["phone"]))
+        current = current["next"]
+    return sorted(records, key=lambda record: record[0])
+
+
+def _require_buckets(buckets):
+    if not buckets:
+        raise ValueError("Хеш-таблица должна содержать хотя бы один бакет")
+
+
+def _hash_index(name, bucket_count):
+    """Хеш-функция."""
+    value = 0
+    for character in name:
+        value = (value * 31 + ord(character)) % bucket_count
+    return value
+
+
+def ht_insert(buckets, name, phone):
+    _require_buckets(buckets)
+    index = _hash_index(name, len(buckets))
+    buckets[index] = ll_insert(buckets[index], name, phone)
+
+
+def ht_find(buckets, name):
+    _require_buckets(buckets)
+    return ll_find(buckets[_hash_index(name, len(buckets))], name)
+
+
+def ht_delete(buckets, name):
+    _require_buckets(buckets)
+    index = _hash_index(name, len(buckets))
+    buckets[index] = ll_delete(buckets[index], name)
+
+
+def ht_list_all(buckets):
+    _require_buckets(buckets)
+    records = []
+    for head in buckets:
+        records.extend(ll_list_all(head))
+    return sorted(records, key=lambda record: record[0])
+
+
+def _bst_node(name, phone):
+    return {"name": name, "phone": phone, "left": None, "right": None}
+
+
+def bst_insert(root, name, phone):
+    if root is None:
+        return _bst_node(name, phone)
+
+    current = root
+    while True:
+        if name == current["name"]:
+            current["phone"] = phone
+            return root
+        side = "left" if name < current["name"] else "right"
+        if current[side] is None:
+            current[side] = _bst_node(name, phone)
+            return root
+        current = current[side]
+
+
+def bst_find(root, name):
+    current = root
+    while current is not None:
+        if name == current["name"]:
+            return current["phone"]
+        current = current["left"] if name < current["name"] else current["right"]
+    return None
+
+
+def bst_delete(root, name):
+    parent = None
+    current = root
+    while current is not None and current["name"] != name:
+        parent = current
+        current = current["left"] if name < current["name"] else current["right"]
+    if current is None:
+        return root
+
+    if current["left"] is not None and current["right"] is not None:
+        successor_parent = current
+        successor = current["right"]
+        while successor["left"] is not None:
+            successor_parent = successor
+            successor = successor["left"]
+        current["name"], current["phone"] = successor["name"], successor["phone"]
+        parent, current = successor_parent, successor
+
+    child = current["left"] if current["left"] is not None else current["right"]
+    if parent is None:
+        return child
+    if parent["left"] is current:
+        parent["left"] = child
+    else:
+        parent["right"] = child
+    return root
+
+
+def bst_list_all(root):
+    records, stack = [], []
+    current = root
+    while stack or current is not None:
+        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
diff --git a/SmirnovVS/docs/data/1-st-exercize/plot_results.py b/SmirnovVS/docs/data/1-st-exercize/plot_results.py
new file mode 100644
index 0000000..606a834
--- /dev/null
+++ b/SmirnovVS/docs/data/1-st-exercize/plot_results.py
@@ -0,0 +1,32 @@
+import csv
+from pathlib import Path
+
+import matplotlib.pyplot as plt
+
+
+def create_plot(csv_path="docs/data/results_summary.csv", output_path="docs/data/performance.png"):
+    with Path(csv_path).open(encoding="utf-8-sig") as file:
+        rows = list(csv.DictReader(file))
+    operations = ["insert", "find_110", "delete_50"]
+    titles = ["Вставка всех записей", "Поиск 110 имён", "Удаление 50 записей"]
+    labels = [(structure, mode) for mode in ("shuffled", "sorted") for structure in ("LinkedList", "HashTable", "BST")]
+    figure, axes = plt.subplots(1, 3, figsize=(15, 5))
+    for axis, operation, title in zip(axes, operations, titles):
+        values = []
+        for structure, mode in labels:
+            row = next(item for item in rows if item["structure"] == structure and item["mode"] == mode and item["operation"] == operation)
+            values.append(float(row["mean_seconds"]) * 1000)
+        axis.bar(range(len(labels)), values, color=["#4472C4", "#70AD47", "#ED7D31"] * 2)
+        axis.set_title(title)
+        axis.set_ylabel("Время, мс")
+        axis.set_xticks(range(len(labels)), [f"{s}\n{m}" for s, m in labels], rotation=35, ha="right")
+        axis.grid(axis="y", alpha=0.25)
+    figure.suptitle("Производительность структур данных (средние значения)")
+    figure.tight_layout()
+    figure.savefig(output_path, dpi=180)
+    plt.close(figure)
+    return Path(output_path)
+
+
+if __name__ == "__main__":
+    print(f"График сохранён: {create_plot()}")
diff --git a/SmirnovVS/docs/data/1-st-exercize/results_raw.csv b/SmirnovVS/docs/data/1-st-exercize/results_raw.csv
new file mode 100644
index 0000000..9fa86ec
--- /dev/null
+++ b/SmirnovVS/docs/data/1-st-exercize/results_raw.csv
@@ -0,0 +1,91 @@
+structure,mode,operation,run,time_seconds
+LinkedList,shuffled,insert,1,0.1947654000005059
+LinkedList,shuffled,find_110,1,0.0063459000002694665
+LinkedList,shuffled,delete_50,1,0.002933899999334244
+LinkedList,shuffled,insert,2,0.19509340000058728
+LinkedList,shuffled,find_110,2,0.006126699999185803
+LinkedList,shuffled,delete_50,2,0.002876999999898544
+LinkedList,shuffled,insert,3,0.19163060000028054
+LinkedList,shuffled,find_110,3,0.00638989999970363
+LinkedList,shuffled,delete_50,3,0.0027322000005369773
+LinkedList,shuffled,insert,4,0.19537710000076913
+LinkedList,shuffled,find_110,4,0.00553089999993972
+LinkedList,shuffled,delete_50,4,0.00274009999975533
+LinkedList,shuffled,insert,5,0.19868119999955525
+LinkedList,shuffled,find_110,5,0.006262500000048021
+LinkedList,shuffled,delete_50,5,0.0034435999996276223
+HashTable,shuffled,insert,1,0.0045235999996293685
+HashTable,shuffled,find_110,1,0.00012590000005729962
+HashTable,shuffled,delete_50,1,6.089999988034833e-05
+HashTable,shuffled,insert,2,0.004393600000184961
+HashTable,shuffled,find_110,2,0.00011859999995067483
+HashTable,shuffled,delete_50,2,5.79999996261904e-05
+HashTable,shuffled,insert,3,0.0038748000006307848
+HashTable,shuffled,find_110,3,0.00011610000001383014
+HashTable,shuffled,delete_50,3,5.719999990105862e-05
+HashTable,shuffled,insert,4,0.003696299999319308
+HashTable,shuffled,find_110,4,0.00011779999931604834
+HashTable,shuffled,delete_50,4,5.729999975301325e-05
+HashTable,shuffled,insert,5,0.0037232000004223664
+HashTable,shuffled,find_110,5,0.0001156999996965169
+HashTable,shuffled,delete_50,5,5.5900000006658956e-05
+BST,shuffled,insert,1,0.004337399999712943
+BST,shuffled,find_110,1,0.0001140000003942987
+BST,shuffled,delete_50,1,7.019999975454994e-05
+BST,shuffled,insert,2,0.004390000000057626
+BST,shuffled,find_110,2,0.00011150000045745401
+BST,shuffled,delete_50,2,6.52999997328152e-05
+BST,shuffled,insert,3,0.004179900000053749
+BST,shuffled,find_110,3,0.00010879999990720535
+BST,shuffled,delete_50,3,6.070000017643906e-05
+BST,shuffled,insert,4,0.004183999999440857
+BST,shuffled,find_110,4,0.00010620000011840602
+BST,shuffled,delete_50,4,9.539999973640079e-05
+BST,shuffled,insert,5,0.004391600000417384
+BST,shuffled,find_110,5,0.00010419999944133451
+BST,shuffled,delete_50,5,6.630000007135095e-05
+LinkedList,sorted,insert,1,0.19158669999978883
+LinkedList,sorted,find_110,1,0.006112799999755225
+LinkedList,sorted,delete_50,1,0.005895900000723486
+LinkedList,sorted,insert,2,0.19256610000047658
+LinkedList,sorted,find_110,2,0.006044900000233611
+LinkedList,sorted,delete_50,2,0.002797499999360298
+LinkedList,sorted,insert,3,0.19292270000005374
+LinkedList,sorted,find_110,3,0.006467600000178209
+LinkedList,sorted,delete_50,3,0.0028355000004012254
+LinkedList,sorted,insert,4,0.19164809999983845
+LinkedList,sorted,find_110,4,0.005796100000225124
+LinkedList,sorted,delete_50,4,0.0030335999999806518
+LinkedList,sorted,insert,5,0.1920518999995693
+LinkedList,sorted,find_110,5,0.006033799999386247
+LinkedList,sorted,delete_50,5,0.0028001999999105465
+HashTable,sorted,insert,1,0.0036538000003929483
+HashTable,sorted,find_110,1,0.0001173999999082298
+HashTable,sorted,delete_50,1,5.810000038763974e-05
+HashTable,sorted,insert,2,0.003586599999835016
+HashTable,sorted,find_110,2,0.00011629999971773941
+HashTable,sorted,delete_50,2,5.540000074688578e-05
+HashTable,sorted,insert,3,0.00354940000033821
+HashTable,sorted,find_110,3,0.00011549999999260763
+HashTable,sorted,delete_50,3,5.520000013348181e-05
+HashTable,sorted,insert,4,0.0036109000002397806
+HashTable,sorted,find_110,4,0.00011329999961162684
+HashTable,sorted,delete_50,4,5.6000000768108293e-05
+HashTable,sorted,insert,5,0.003564399999959278
+HashTable,sorted,find_110,5,0.00011339999946358148
+HashTable,sorted,delete_50,5,5.480000072566327e-05
+BST,sorted,insert,1,0.3111501000003045
+BST,sorted,find_110,1,0.007159199999478005
+BST,sorted,delete_50,1,0.004548900000372669
+BST,sorted,insert,2,0.30066009999973176
+BST,sorted,find_110,2,0.008023899999898276
+BST,sorted,delete_50,2,0.004239900000357011
+BST,sorted,insert,3,0.3020464000001084
+BST,sorted,find_110,3,0.00876090000019758
+BST,sorted,delete_50,3,0.004445499999746971
+BST,sorted,insert,4,0.30183889999989333
+BST,sorted,find_110,4,0.007328300000153831
+BST,sorted,delete_50,4,0.005208799999309122
+BST,sorted,insert,5,0.3034312999998292
+BST,sorted,find_110,5,0.008107399999971676
+BST,sorted,delete_50,5,0.004352900000412774
diff --git a/SmirnovVS/docs/data/1-st-exercize/results_summary.csv b/SmirnovVS/docs/data/1-st-exercize/results_summary.csv
new file mode 100644
index 0000000..b0a163e
--- /dev/null
+++ b/SmirnovVS/docs/data/1-st-exercize/results_summary.csv
@@ -0,0 +1,19 @@
+structure,mode,operation,mean_seconds
+LinkedList,shuffled,insert,0.19510954000033962
+LinkedList,shuffled,find_110,0.006131179999829328
+LinkedList,shuffled,delete_50,0.0029453599998305437
+HashTable,shuffled,insert,0.004042300000037358
+HashTable,shuffled,find_110,0.00011881999980687397
+HashTable,shuffled,delete_50,5.7859999833453914e-05
+BST,shuffled,insert,0.004296579999936512
+BST,shuffled,find_110,0.00010894000006373971
+BST,shuffled,delete_50,7.157999989431119e-05
+LinkedList,sorted,insert,0.19215509999994537
+LinkedList,sorted,find_110,0.006091039999955683
+LinkedList,sorted,delete_50,0.0034725400000752416
+HashTable,sorted,insert,0.0035930200001530466
+HashTable,sorted,find_110,0.00011517999973875703
+HashTable,sorted,delete_50,5.590000055235578e-05
+BST,sorted,insert,0.30382535999997345
+BST,sorted,find_110,0.007875939999939874
+BST,sorted,delete_50,0.004559200000039709
diff --git a/SmirnovVS/docs/data/2-nd-exercize/experiment.py b/SmirnovVS/docs/data/2-nd-exercize/experiment.py
new file mode 100644
index 0000000..4024058
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/experiment.py
@@ -0,0 +1,64 @@
+import argparse
+import csv
+from pathlib import Path
+from statistics import mean
+
+from generate_mazes import generate_all
+from maze_app import AStarStrategy, BFSStrategy, DFSStrategy, MazeSolver, TextFileMazeBuilder
+
+
+STRATEGIES = (BFSStrategy, DFSStrategy, AStarStrategy)
+
+
+def run_experiment(repeats=7, maze_dir="mazes", output_dir="docs/data"):
+    generate_all(maze_dir)
+    builder = TextFileMazeBuilder()
+    rows = []
+    for maze_path in sorted(Path(maze_dir).glob("*.txt")):
+        maze = builder.build_from_file(maze_path)
+        for strategy_type in STRATEGIES:
+            for run in range(1, repeats + 1):
+                stats = MazeSolver(maze, strategy_type()).solve()
+                rows.append({
+                    "maze": maze_path.stem,
+                    "strategy": stats.strategy,
+                    "run": run,
+                    "time_ms": stats.time_ms,
+                    "visited_cells": stats.visited_cells,
+                    "path_length": stats.path_length,
+                    "path_found": bool(stats.path),
+                })
+    output = Path(output_dir)
+    output.mkdir(parents=True, exist_ok=True)
+    raw_path = output / "maze_results_raw.csv"
+    with raw_path.open("w", newline="", encoding="utf-8-sig") as file:
+        writer = csv.DictWriter(file, fieldnames=rows[0].keys())
+        writer.writeheader()
+        writer.writerows(rows)
+
+    groups = {}
+    for row in rows:
+        groups.setdefault((row["maze"], row["strategy"]), []).append(row)
+    summary = []
+    for (maze_name, strategy), values in groups.items():
+        summary.append({
+            "maze": maze_name,
+            "strategy": strategy,
+            "mean_time_ms": mean(row["time_ms"] for row in values),
+            "mean_visited_cells": mean(row["visited_cells"] for row in values),
+            "path_length": values[0]["path_length"],
+            "path_found": values[0]["path_found"],
+        })
+    summary_path = output / "maze_results_summary.csv"
+    with summary_path.open("w", newline="", encoding="utf-8-sig") as file:
+        writer = csv.DictWriter(file, fieldnames=summary[0].keys())
+        writer.writeheader()
+        writer.writerows(summary)
+    return raw_path, summary_path
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Сравнение алгоритмов поиска пути")
+    parser.add_argument("--repeats", type=int, default=7)
+    args = parser.parse_args()
+    print("Результаты:", *run_experiment(args.repeats), sep="\n")
diff --git a/SmirnovVS/docs/data/2-nd-exercize/generate_mazes.py b/SmirnovVS/docs/data/2-nd-exercize/generate_mazes.py
new file mode 100644
index 0000000..b9fb1c3
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/generate_mazes.py
@@ -0,0 +1,52 @@
+"""Генерация воспроизводимых тестовых лабиринтов."""
+
+import random
+from pathlib import Path
+
+
+def obstacle_maze(width, height, wall_probability, seed):
+    rng = random.Random(seed)
+    grid = [["#" if x in (0, width - 1) or y in (0, height - 1) else " " for x in range(width)] for y in range(height)]
+    for y in range(1, height - 1):
+        for x in range(1, width - 1):
+            if rng.random() < wall_probability:
+                grid[y][x] = "#"
+    # Оставляем гарантированный путь по верхней и правой внутренним границам.
+    for x in range(1, width - 1):
+        grid[1][x] = " "
+    for y in range(1, height - 1):
+        grid[y][width - 2] = " "
+    grid[1][1], grid[height - 2][width - 2] = "S", "E"
+    return "\n".join("".join(row) for row in grid) + "\n"
+
+
+def empty_maze(width=50, height=50):
+    return obstacle_maze(width, height, 0, 1)
+
+
+def blocked_maze(width=30, height=30):
+    lines = empty_maze(width, height).splitlines()
+    grid = [list(line) for line in lines]
+    exit_y, exit_x = height - 2, width - 2
+    grid[exit_y - 1][exit_x] = "#"
+    grid[exit_y][exit_x - 1] = "#"
+    return "\n".join("".join(row) for row in grid) + "\n"
+
+
+def generate_all(output_dir="mazes"):
+    output = Path(output_dir)
+    output.mkdir(parents=True, exist_ok=True)
+    maps = {
+        "small_10x10.txt": obstacle_maze(10, 10, 0.12, 10),
+        "medium_50x50.txt": obstacle_maze(50, 50, 0.28, 50),
+        "large_100x100.txt": obstacle_maze(100, 100, 0.32, 100),
+        "empty_50x50.txt": empty_maze(),
+        "no_path_30x30.txt": blocked_maze(),
+    }
+    for filename, content in maps.items():
+        (output / filename).write_text(content, encoding="utf-8")
+    return list(maps)
+
+
+if __name__ == "__main__":
+    print("Созданы файлы:", ", ".join(generate_all()))
diff --git a/SmirnovVS/docs/data/2-nd-exercize/main.py b/SmirnovVS/docs/data/2-nd-exercize/main.py
new file mode 100644
index 0000000..a118385
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/main.py
@@ -0,0 +1,24 @@
+import argparse
+
+from maze_app import AStarStrategy, BFSStrategy, ConsoleView, DFSStrategy, MazeSolver, TextFileMazeBuilder
+
+
+STRATEGIES = {"bfs": BFSStrategy, "dfs": DFSStrategy, "astar": AStarStrategy}
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Поиск выхода из лабиринта")
+    parser.add_argument("maze", nargs="?", default="mazes/small_10x10.txt")
+    parser.add_argument("--algorithm", choices=STRATEGIES, default="bfs")
+    args = parser.parse_args()
+    maze = TextFileMazeBuilder().build_from_file(args.maze)
+    view = ConsoleView()
+    solver = MazeSolver(maze, STRATEGIES[args.algorithm]())
+    solver.attach(view)
+    stats = solver.solve()
+    print(view.render(maze, stats.path))
+    print(f"Время: {stats.time_ms:.4f} мс; посещено: {stats.visited_cells}; длина пути: {stats.path_length}")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/SmirnovVS/docs/data/2-nd-exercize/maze_app.py b/SmirnovVS/docs/data/2-nd-exercize/maze_app.py
new file mode 100644
index 0000000..7335613
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/maze_app.py
@@ -0,0 +1,246 @@
+"""Модель лабиринта и алгоритмы поиска с паттернами Builder, Strategy, Observer."""
+
+from abc import ABC, abstractmethod
+from collections import deque
+from dataclasses import dataclass, field
+from heapq import heappop, heappush
+from itertools import count
+from pathlib import Path
+from time import perf_counter
+
+
+@dataclass(frozen=True)
+class Cell:
+    x: int
+    y: int
+    is_wall: bool = False
+    is_start: bool = False
+    is_exit: bool = False
+
+    def is_passable(self):
+        return not self.is_wall
+
+
+class Maze:
+    def __init__(self, cells):
+        if not cells or not cells[0]:
+            raise ValueError("Лабиринт не может быть пустым")
+        self.cells = cells
+        self.height = len(cells)
+        self.width = len(cells[0])
+        self.start = next((cell for row in cells for cell in row if cell.is_start), None)
+        self.exit = next((cell for row in cells for cell in row if cell.is_exit), None)
+
+    def get_cell(self, x, y):
+        if 0 <= x < self.width and 0 <= y < self.height:
+            return self.cells[y][x]
+        return None
+
+    def get_neighbors(self, cell):
+        neighbors = []
+        for dx, dy in ((0, -1), (1, 0), (0, 1), (-1, 0)):
+            neighbor = self.get_cell(cell.x + dx, cell.y + dy)
+            if neighbor is not None and neighbor.is_passable():
+                neighbors.append(neighbor)
+        return neighbors
+
+
+class MazeBuilder(ABC):
+    @abstractmethod
+    def build_from_file(self, filename):
+        pass
+
+
+class TextFileMazeBuilder(MazeBuilder):
+    SYMBOLS = {"#", " ", "S", "E"}
+
+    def build_from_file(self, filename):
+        lines = Path(filename).read_text(encoding="utf-8").splitlines()
+        if not lines or not lines[0] or any(len(line) != len(lines[0]) for line in lines):
+            raise ValueError("Строки лабиринта должны иметь одинаковую ненулевую длину")
+        unknown = {character for line in lines for character in line} - self.SYMBOLS
+        if unknown:
+            raise ValueError(f"Недопустимые символы: {sorted(unknown)}")
+        if sum(line.count("S") for line in lines) != 1 or sum(line.count("E") for line in lines) != 1:
+            raise ValueError("Лабиринт должен содержать ровно один старт S и один выход E")
+
+        cells = []
+        for y, line in enumerate(lines):
+            cells.append([
+                Cell(x, y, symbol == "#", symbol == "S", symbol == "E")
+                for x, symbol in enumerate(line)
+            ])
+        return Maze(cells)
+
+
+class PathFindingStrategy(ABC):
+    name = "Неизвестно"
+
+    def __init__(self):
+        self.visited_count = 0
+
+    @abstractmethod
+    def find_path(self, maze, start, exit_cell):
+        pass
+
+    @staticmethod
+    def restore_path(parent, start, exit_cell):
+        if exit_cell not in parent:
+            return []
+        path, current = [], exit_cell
+        while current is not None:
+            path.append(current)
+            current = parent[current]
+        path.reverse()
+        return path if path and path[0] == start else []
+
+
+class BFSStrategy(PathFindingStrategy):
+    name = "BFS"
+
+    def find_path(self, maze, start, exit_cell):
+        queue = deque([start])
+        parent = {start: None}
+        visited = 0
+        while queue:
+            current = queue.popleft()
+            visited += 1
+            if current == exit_cell:
+                break
+            for neighbor in maze.get_neighbors(current):
+                if neighbor not in parent:
+                    parent[neighbor] = current
+                    queue.append(neighbor)
+        self.visited_count = visited
+        return self.restore_path(parent, start, exit_cell)
+
+
+class DFSStrategy(PathFindingStrategy):
+    name = "DFS"
+
+    def find_path(self, maze, start, exit_cell):
+        stack = [start]
+        parent = {start: None}
+        visited = 0
+        while stack:
+            current = stack.pop()
+            visited += 1
+            if current == exit_cell:
+                break
+            for neighbor in maze.get_neighbors(current):
+                if neighbor not in parent:
+                    parent[neighbor] = current
+                    stack.append(neighbor)
+        self.visited_count = visited
+        return self.restore_path(parent, start, exit_cell)
+
+
+class AStarStrategy(PathFindingStrategy):
+    name = "A*"
+
+    @staticmethod
+    def heuristic(first, second):
+        return abs(first.x - second.x) + abs(first.y - second.y)
+
+    def find_path(self, maze, start, exit_cell):
+        order = count()
+        queue = [(self.heuristic(start, exit_cell), next(order), start)]
+        distance = {start: 0}
+        parent = {start: None}
+        closed = set()
+        while queue:
+            _, _, current = heappop(queue)
+            if current in closed:
+                continue
+            closed.add(current)
+            if current == exit_cell:
+                break
+            for neighbor in maze.get_neighbors(current):
+                new_distance = distance[current] + 1
+                if new_distance < distance.get(neighbor, float("inf")):
+                    distance[neighbor] = new_distance
+                    parent[neighbor] = current
+                    priority = new_distance + self.heuristic(neighbor, exit_cell)
+                    heappush(queue, (priority, next(order), neighbor))
+        self.visited_count = len(closed)
+        return self.restore_path(parent, start, exit_cell)
+
+
+@dataclass
+class SearchStats:
+    strategy: str
+    time_ms: float
+    visited_cells: int
+    path_length: int
+    path: list = field(repr=False)
+
+
+class Observer(ABC):
+    @abstractmethod
+    def update(self, event):
+        pass
+
+
+class ConsoleView(Observer):
+    def __init__(self, verbose=True):
+        self.verbose = verbose
+        self.events = []
+
+    def update(self, event):
+        self.events.append(event)
+        if self.verbose:
+            print(event["message"])
+
+    def render(self, maze, path=None):
+        path_cells = set(path or [])
+        rows = []
+        for row in maze.cells:
+            symbols = []
+            for cell in row:
+                if cell.is_start:
+                    symbols.append("S")
+                elif cell.is_exit:
+                    symbols.append("E")
+                elif cell.is_wall:
+                    symbols.append("#")
+                elif cell in path_cells:
+                    symbols.append(".")
+                else:
+                    symbols.append(" ")
+            rows.append("".join(symbols))
+        return "\n".join(rows)
+
+
+class MazeSolver:
+    def __init__(self, maze, strategy):
+        self.maze = maze
+        self.strategy = strategy
+        self.observers = []
+
+    def set_strategy(self, strategy):
+        self.strategy = strategy
+
+    def attach(self, observer):
+        if observer not in self.observers:
+            self.observers.append(observer)
+
+    def notify(self, event):
+        for observer in self.observers:
+            observer.update(event)
+
+    def solve(self):
+        self.notify({"type": "search_started", "message": f"Запущен алгоритм {self.strategy.name}"})
+        started = perf_counter()
+        path = self.strategy.find_path(self.maze, self.maze.start, self.maze.exit)
+        elapsed_ms = max((perf_counter() - started) * 1000, 1e-9)
+        stats = SearchStats(
+            strategy=self.strategy.name,
+            time_ms=elapsed_ms,
+            visited_cells=self.strategy.visited_count,
+            path_length=max(len(path) - 1, 0),
+            path=path,
+        )
+        event_type = "path_found" if path else "path_not_found"
+        message = f"{self.strategy.name}: путь длиной {stats.path_length}" if path else f"{self.strategy.name}: путь не найден"
+        self.notify({"type": event_type, "message": message, "stats": stats})
+        return stats
diff --git a/SmirnovVS/docs/data/2-nd-exercize/maze_results_raw.csv b/SmirnovVS/docs/data/2-nd-exercize/maze_results_raw.csv
new file mode 100644
index 0000000..7bdeffe
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/maze_results_raw.csv
@@ -0,0 +1,106 @@
+maze,strategy,run,time_ms,visited_cells,path_length,path_found
+empty_50x50,BFS,1,28.560300008393824,2304,94,True
+empty_50x50,BFS,2,21.739099989645183,2304,94,True
+empty_50x50,BFS,3,28.969400038477033,2304,94,True
+empty_50x50,BFS,4,26.839600002858788,2304,94,True
+empty_50x50,BFS,5,16.788399952929467,2304,94,True
+empty_50x50,BFS,6,14.332599996123463,2304,94,True
+empty_50x50,BFS,7,22.064500022679567,2304,94,True
+empty_50x50,DFS,1,0.5307000246830285,95,94,True
+empty_50x50,DFS,2,0.6820000126026571,95,94,True
+empty_50x50,DFS,3,0.5209000082686543,95,94,True
+empty_50x50,DFS,4,0.5133000086061656,95,94,True
+empty_50x50,DFS,5,0.8089999901130795,95,94,True
+empty_50x50,DFS,6,0.5200000014156103,95,94,True
+empty_50x50,DFS,7,0.8933999924920499,95,94,True
+empty_50x50,A*,1,68.07579996529967,2304,94,True
+empty_50x50,A*,2,61.01420003687963,2304,94,True
+empty_50x50,A*,3,52.171000046655536,2304,94,True
+empty_50x50,A*,4,53.36979997809976,2304,94,True
+empty_50x50,A*,5,64.77910000830889,2304,94,True
+empty_50x50,A*,6,51.02490005083382,2304,94,True
+empty_50x50,A*,7,70.88650000514463,2304,94,True
+large_100x100,BFS,1,91.43029997358099,6409,194,True
+large_100x100,BFS,2,98.55669998796657,6409,194,True
+large_100x100,BFS,3,98.43990002991632,6409,194,True
+large_100x100,BFS,4,51.18469998706132,6409,194,True
+large_100x100,BFS,5,44.218000024557114,6409,194,True
+large_100x100,BFS,6,28.500600019469857,6409,194,True
+large_100x100,BFS,7,60.57189998682588,6409,194,True
+large_100x100,DFS,1,25.9578000404872,1561,762,True
+large_100x100,DFS,2,18.451499985530972,1561,762,True
+large_100x100,DFS,3,18.506099993828684,1561,762,True
+large_100x100,DFS,4,14.582899981178343,1561,762,True
+large_100x100,DFS,5,10.724799998570234,1561,762,True
+large_100x100,DFS,6,17.07870000973344,1561,762,True
+large_100x100,DFS,7,19.463400007225573,1561,762,True
+large_100x100,A*,1,38.1690000067465,1997,194,True
+large_100x100,A*,2,30.891000002156943,1997,194,True
+large_100x100,A*,3,23.280899971723557,1997,194,True
+large_100x100,A*,4,26.04500000597909,1997,194,True
+large_100x100,A*,5,27.82869996735826,1997,194,True
+large_100x100,A*,6,26.94000001065433,1997,194,True
+large_100x100,A*,7,28.832400043029338,1997,194,True
+medium_50x50,BFS,1,6.693199975416064,1700,94,True
+medium_50x50,BFS,2,6.831499980762601,1700,94,True
+medium_50x50,BFS,3,8.055799989961088,1700,94,True
+medium_50x50,BFS,4,7.26869999198243,1700,94,True
+medium_50x50,BFS,5,11.507100018206984,1700,94,True
+medium_50x50,BFS,6,7.060799980536103,1700,94,True
+medium_50x50,BFS,7,7.459699991159141,1700,94,True
+medium_50x50,DFS,1,3.0005000298842788,408,266,True
+medium_50x50,DFS,2,1.8214000156149268,408,266,True
+medium_50x50,DFS,3,2.6385000091977417,408,266,True
+medium_50x50,DFS,4,1.7798999906517565,408,266,True
+medium_50x50,DFS,5,1.7468000296503305,408,266,True
+medium_50x50,DFS,6,1.7085999716073275,408,266,True
+medium_50x50,DFS,7,1.7067999579012394,408,266,True
+medium_50x50,A*,1,8.779299969319254,942,94,True
+medium_50x50,A*,2,9.8794000223279,942,94,True
+medium_50x50,A*,3,9.167099953629076,942,94,True
+medium_50x50,A*,4,16.693999990820885,942,94,True
+medium_50x50,A*,5,12.841499992646277,942,94,True
+medium_50x50,A*,6,23.23459996841848,942,94,True
+medium_50x50,A*,7,18.193199997767806,942,94,True
+no_path_30x30,BFS,1,3.5794000141322613,781,0,False
+no_path_30x30,BFS,2,3.4125999663956463,781,0,False
+no_path_30x30,BFS,3,3.811199974734336,781,0,False
+no_path_30x30,BFS,4,3.524600004311651,781,0,False
+no_path_30x30,BFS,5,3.535500029101968,781,0,False
+no_path_30x30,BFS,6,3.6441999836824834,781,0,False
+no_path_30x30,BFS,7,3.4087999956682324,781,0,False
+no_path_30x30,DFS,1,3.3659999608062208,781,0,False
+no_path_30x30,DFS,2,3.659199981484562,781,0,False
+no_path_30x30,DFS,3,3.4770999918691814,781,0,False
+no_path_30x30,DFS,4,3.4067999804392457,781,0,False
+no_path_30x30,DFS,5,3.334700013510883,781,0,False
+no_path_30x30,DFS,6,3.7082999479025602,781,0,False
+no_path_30x30,DFS,7,5.642200005240738,781,0,False
+no_path_30x30,A*,1,7.9901000135578215,781,0,False
+no_path_30x30,A*,2,8.304700022563338,781,0,False
+no_path_30x30,A*,3,11.212200042791665,781,0,False
+no_path_30x30,A*,4,14.160500024445355,781,0,False
+no_path_30x30,A*,5,9.939100011251867,781,0,False
+no_path_30x30,A*,6,8.455800008960068,781,0,False
+no_path_30x30,A*,7,7.638900016900152,781,0,False
+small_10x10,BFS,1,0.18330005696043372,58,14,True
+small_10x10,BFS,2,0.14630000805482268,58,14,True
+small_10x10,BFS,3,0.18289999570697546,58,14,True
+small_10x10,BFS,4,0.14349998673424125,58,14,True
+small_10x10,BFS,5,0.14270003885030746,58,14,True
+small_10x10,BFS,6,0.1477000187151134,58,14,True
+small_10x10,BFS,7,0.14270003885030746,58,14,True
+small_10x10,DFS,1,0.042700034100562334,15,14,True
+small_10x10,DFS,2,0.04120002267882228,15,14,True
+small_10x10,DFS,3,0.041000021155923605,15,14,True
+small_10x10,DFS,4,0.04099996294826269,15,14,True
+small_10x10,DFS,5,0.04079996142536402,15,14,True
+small_10x10,DFS,6,0.04060001811012626,15,14,True
+small_10x10,DFS,7,0.04060001811012626,15,14,True
+small_10x10,A*,1,0.30999997397884727,58,14,True
+small_10x10,A*,2,0.30529999639838934,58,14,True
+small_10x10,A*,3,0.325299974065274,58,14,True
+small_10x10,A*,4,0.31670002499595284,58,14,True
+small_10x10,A*,5,0.32130000181496143,58,14,True
+small_10x10,A*,6,0.3467000206001103,58,14,True
+small_10x10,A*,7,0.33109996002167463,58,14,True
diff --git a/SmirnovVS/docs/data/2-nd-exercize/maze_results_summary.csv b/SmirnovVS/docs/data/2-nd-exercize/maze_results_summary.csv
new file mode 100644
index 0000000..15e6f68
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/maze_results_summary.csv
@@ -0,0 +1,16 @@
+maze,strategy,mean_time_ms,mean_visited_cells,path_length,path_found
+empty_50x50,BFS,22.75627143015819,2304,94,True
+empty_50x50,DFS,0.6384714340258922,95,94,True
+empty_50x50,A*,60.188757155888844,2304,94,True
+large_100x100,BFS,67.55744285848257,6409,194,True
+large_100x100,DFS,17.82360000236492,1561,762,True
+large_100x100,A*,28.85528571537829,1997,194,True
+medium_50x50,BFS,7.83954284686063,1700,94,True
+medium_50x50,DFS,2.0575000006439432,408,266,True
+medium_50x50,A*,14.112728556418526,942,94,True
+no_path_30x30,BFS,3.559471424003797,781,0,False
+no_path_30x30,DFS,3.799185697321913,781,0,False
+no_path_30x30,A*,9.671614305781466,781,0,False
+small_10x10,BFS,0.1555857348388859,58,14,True
+small_10x10,DFS,0.041128576932741065,15,14,True
+small_10x10,A*,0.3223428502678871,58,14,True
diff --git a/SmirnovVS/docs/data/2-nd-exercize/plot_results.py b/SmirnovVS/docs/data/2-nd-exercize/plot_results.py
new file mode 100644
index 0000000..1c262cc
--- /dev/null
+++ b/SmirnovVS/docs/data/2-nd-exercize/plot_results.py
@@ -0,0 +1,35 @@
+import csv
+from pathlib import Path
+
+import matplotlib.pyplot as plt
+
+
+def create_plot(csv_path="docs/data/maze_results_summary.csv", output_path="docs/data/maze_performance.png"):
+    with Path(csv_path).open(encoding="utf-8-sig") as file:
+        rows = list(csv.DictReader(file))
+    mazes = sorted({row["maze"] for row in rows})
+    strategies = ["BFS", "DFS", "A*"]
+    colors = {"BFS": "#4472C4", "DFS": "#ED7D31", "A*": "#70AD47"}
+    figure, axes = plt.subplots(2, 1, figsize=(12, 9))
+    positions = range(len(mazes))
+    width = 0.24
+    for index, strategy in enumerate(strategies):
+        selected = [next(row for row in rows if row["maze"] == maze and row["strategy"] == strategy) for maze in mazes]
+        offsets = [position + (index - 1) * width for position in positions]
+        axes[0].bar(offsets, [float(row["mean_time_ms"]) for row in selected], width, label=strategy, color=colors[strategy])
+        axes[1].bar(offsets, [float(row["mean_visited_cells"]) for row in selected], width, label=strategy, color=colors[strategy])
+    for axis, ylabel, title in zip(axes, ["Время, мс", "Посещено клеток"], ["Среднее время поиска", "Объём исследования лабиринта"]):
+        axis.set_xticks(list(positions), mazes, rotation=20, ha="right")
+        axis.set_ylabel(ylabel)
+        axis.set_title(title)
+        axis.grid(axis="y", alpha=0.25)
+        axis.legend()
+    figure.suptitle("Сравнение стратегий поиска (средние значения)")
+    figure.tight_layout()
+    figure.savefig(output_path, dpi=180)
+    plt.close(figure)
+    return Path(output_path)
+
+
+if __name__ == "__main__":
+    print(f"График сохранён: {create_plot()}")
diff --git a/SmirnovVS/docs/maze_performance.png b/SmirnovVS/docs/maze_performance.png
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diff --git a/SmirnovVS/docs/Поиск пути в лабиринте.docx b/SmirnovVS/docs/Поиск пути в лабиринте.docx
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diff --git a/SmirnovVS/docs/Структуры данных.docx b/SmirnovVS/docs/Структуры данных.docx
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