def main():
    N = int(input())
    board = [list(input()) for _ in range(N)]

    reach_ctr = 0
    for row in board:
        if "." in row and row.count("A") == N - 1:
            reach_ctr += 1

    for c_idx in range(N):
        ctr = [0, 0]
        for r_idx in range(N):
            match board[r_idx][c_idx]:
                case "B":
                    break
                case ".":
                    ctr[1] += 1
                case "A":
                    ctr[0] += 1
        else:
            if ctr[0] == N - 1 and ctr[1] == 1:
                reach_ctr += 1
    ctr = [0, 0]
    for idx in range(N):
        match board[idx][idx]:
            case "B":
                break
            case ".":
                ctr[1] += 1
            case "A":
                ctr[0] += 1
    else:
        if ctr[0] == N - 1 and ctr[1] == 1:
            reach_ctr += 1

    ctr = [0, 0]
    for idx in range(N):
        match board[idx][N - 1 - idx]:
            case "B":
                break
            case ".":
                ctr[1] += 1
            case "A":
                ctr[0] += 1
    else:
        if ctr[0] == N - 1 and ctr[1] == 1:
            reach_ctr += 1
    print(reach_ctr)


if __name__ == "__main__":
    main()