from collections import deque

def shortest_path_binary_matrix(grid: list[list[int]]) -> int:
    n = len(grid)
    if grid[0][0] == 1 or grid[n-1][n-1] == 1:
        return -1

    queue = deque([(0, 0, 1)])  # (row, col, distance)
    grid[0][0] = 1  # mark visited

    directions = [(0,1),(0,-1),(1,0),(-1,0),(1,1),(1,-1),(-1,1),(-1,-1)]

    while queue:
        r, c, dist = queue.popleft()

        if r == n - 1 and c == n - 1:
            return dist

        for dr, dc in directions:
            nr, nc = r + dr, c + dc
            if 0 <= nr < n and 0 <= nc < n and grid[nr][nc] == 0:
                grid[nr][nc] = 1  # mark visited
                queue.append((nr, nc, dist + 1))

    return -1

# Time: O(n^2), Space: O(n^2)

Graphs — BFS, DFS, Topological Sort

Graphs — BFS, DFS, Topological Sort

Graphs — BFS, DFS, Topological Sort