H, W = map(int, input().split())

C = []


def print_mat(c):
    for l in c:
        print(l)


for h in range(H):
    C.append(input())
sl = [[0] * W for _ in range(H)]
gl = [[0] * W for _ in range(H)]
sl[0][0] = 1
gl[-1][-1] = 1

max_sw = 0
max_sh = 0
for h in range(H):
    for w in range(W):
        if C[h][w] == "#":
            continue
        if h > 0 and sl[h - 1][w] != 0:
            sl[h][w] = 1
            if max_sh < h:
                max_sh = h
        if w > 0 and sl[h][w - 1] != 0:
            sl[h][w] = 1
            if max_sw < w:
                max_sw = w
min_gw = W - 1
min_gh = H - 1
for h in reversed(range(H)):
    for w in reversed(range(W)):
        if C[h][w] == "#":
            continue
        if h < H - 1 and gl[h + 1][w] != 0:
            gl[h][w] = 1
            if min_gh > h:
                min_gh = h
        if w < W - 1 and gl[h][w + 1] != 0:
            gl[h][w] = 1
            if min_gw > w:
                min_gw = w
ans = H + W - 2

if sl[H - 1][W - 1] == 1:
    print(ans)
elif min_gh <= max_sh + 1 or min_gw <= max_sw + 1:
    print(ans + 1)
else:
    print(ans + 2)