D

def gt(n, mt, x, y):
    if(mt & (1 << (y * n + x))):
        return 1
    else:
        return 0

def serch_round(n, mt, x, y):
    if(y + 1 == n):
        u = 1
    else:
        u = 2

    if(y == 0):
        d = 0
    else:
        d = -1

    if(x + 1 == n):
        r = 1
    else:
        r = 2

    if(x == 0):
        l = 0
    else:
        l = -1

    out = -1 * gt(n, mt, x, y)
    for ay in range(y + d, y + u):
        for ax in range(x + l, x + r):
            out += gt(n, mt, ax, ay)
    return out

n = int(input())

now = 0
past = 0

for y in range(n):
    inp = input()
    for x in range(n):
        if(inp[x] == '*'):
            past = past | (1 << (y * n + x))

hist = [past]
ans = 0

while(past):
    for y in range(n):
        for x in range(n):
            if(past & (1 << (y * n + x)) and 2 <= serch_round(n, past, x, y) <= 3):
                now = now  | (1 << (y * n + x))
            if(not past & (1 << (y * n + x)) and serch_round(n, past, x, y) == 3):
                now = now  | (1 << (y * n + x))

    if(hist.count(now)):
        print("Yes")
        ans += 1
        break



    hist.append(now)

    past = now
    now = 0
    ans += 1
else:
    print("No")
print(ans)