def main():
    import sys
    from collections import deque
    input = sys.stdin.readline

    H, W = map(int, input().split())
    grid = []
    for _ in range(H):
        line = input().rstrip('\n')
        grid.append(line)

    d = [(0, 1), (1, 0), (-1, 0), (0, -1)]
    inf = float('inf')
    que = deque()
    que.append((0, 0))
    seen = [[inf] * W for _ in range(H)]
    seen[0][0] = 0
    while que:
        h, w = que.popleft()
        for dh, dw in d:
            h_new, w_new = h+dh, w+dw
            if 0 <= h_new < H and 0 <= w_new < W:
                if seen[h_new][w_new] > 10**9:
                    que.append((h_new, w_new))
                if grid[h_new][w_new] == '.':
                    seen[h_new][w_new] = min(seen[h_new][w_new], seen[h][w] + 1)
                else:
                    seen[h_new][w_new] = min(seen[h_new][w_new], seen[h][w] + 1 + h_new + w_new)
    print(seen[-1][-1])


if __name__ == '__main__':
    main()