Problem:
Score : 400 points

Problem Statement

Snuke has N strings. The i-th string is s_i.

Let us concatenate these strings into one string after arranging them in some order.
Find the maximum possible number of occurrences of AB in the resulting string.

Constraints

1 \leq N \leq 10^{4}

2 \leq |s_i| \leq 10

s_i consists of uppercase English letters.

Input

Input is given from Standard Input in the following format:

N
s_1
\vdots
s_N

Output

Print the answer.

Sample Input 1

3
ABCA
XBAZ
BAD

Sample Output 1

2

For example, if we concatenate ABCA, BAD and XBAZ in this order, the resulting string ABCABADXBAZ has two occurrences of AB.

Sample Input 2

9
BEWPVCRWH
ZZNQYIJX
BAVREA
PA
HJMYITEOX
BCJHMRMNK
BP
QVFABZ
PRGKSPUNA

Sample Output 2

4

Sample Input 3

7
RABYBBE
JOZ
BMHQUVA
BPA
ISU
MCMABAOBHZ
SZMEHMA

Sample Output 3

4

Solution in PyPy3 (2.4.0) (judge verdict: Wrong Answer)

def main():
    N = int(input())
    S = [input() for _ in range(N)]
    ans = 0
    bxa = 0
    bx = 0
    xa = 0
    for s in S:
        ans += s.count("AB")
        if s.startswith("B") and s.endswith("A"):
            bxa += 1
        elif s.startswith("B"):
            bx += 1
        elif s.endswith("A"):
            xa += 1

    ans += min(bx, xa)
    ans += bxa - (1 if max(bx, xa) == 0 else 0)
    print(ans)


if __name__ == "__main__":
    main()