n = int(input())
s = [input() for _ in range(n)]
ans = 0
for _ in range(2):
    for si in s:
        ans += si.count('A') == n - 1 and si.count('.') == 1
    ca = 0
    for i in range(n):
        if s[i][i] == 'A':
            ca += 1
        elif s[i][i] == 'B':
            ca = -3
            break
    ans += ca == n - 1
    s = list(zip(*s))[::-1]
print(ans)