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 00000000..4024058b
--- /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 00000000..b9fb1c31
--- /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 00000000..a1183851
--- /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 00000000..7335613f
--- /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/plot_results.py b/SmirnovVS/docs/data/2-nd-exercize/plot_results.py
new file mode 100644
index 00000000..1c262cc7
--- /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()}")