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 C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;

int main()
{
    int n, cnt = 0, m, a = 0, b = 0, ab = 0;
    vector<string> s;
    cin >> n;
    s.resize(n);
    for (int i = 0; i < n; i++)
    {
        cin >> s[i];
        for (int j = 0; j < s[i].length() - 1; j++)
        {
            if (s[i][j] == 'A' && s[i][j + 1] == 'B')
                cnt++;
        }
        if (s[i][s[i].length() - 1] == 'A')
        {
            a++;
            ab++;
        }
        if (s[i][0] == 'B')
        {
            b++;
            ab++;
        }
        if (ab % 2 != 0)
            ab--;
    }
    m = (a < b) ? a : b;
    cnt += m;
    if (a == b && ab == b)
        cnt--;
    cout << cnt << endl;
    return 0;
}