#############################################################

import sys
sys.setrecursionlimit(10**7)

from heapq import heappop,heappush
from collections import deque,defaultdict,Counter
from bisect import bisect_left, bisect_right
from itertools import product,combinations,permutations

ipt = sys.stdin.readline

def iin():
    return int(ipt())
def lmin():
    return list(map(int,ipt().split()))

MOD = 998244353
#############################################################

N = iin()
S = [input() for _ in range(N)]
ans = 0
for i in range(N):
    cnt = 0
    b = 0
    for j in range(N):
        if S[i][j] == "A":
            cnt += 1
        if S[i][j] == "B":
            b = 1
    
    if cnt == N-1 and not b:
        ans += 1

    cnt = 0
    b = 0
    for j in range(N):
        if S[j][i] == "A":
            cnt += 1
        if S[j][i] == "B":
            b = 1
    if cnt == N-1 and not b:
        ans += 1


cnt = 0
for i in range(N):
    if S[i][i] == "A":
        cnt += 1
    if S[i][i] == "B":
        break
else:
    if cnt == N-1:
        ans += 1

cnt = 0
for i in range(N):
    if S[i][N-i-1] == "A":
        cnt += 1
    if S[i][N-i-1] == "B":
        break
else:
    if cnt == N-1:
        ans += 1

print(ans)