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>
#include <stdio.h>
#include <math.h>
using namespace std;
using vi = vector<int>;
using vll = vector<long long int>;
using vb = vector<bool>;
using vvi = vector<vector<int>>;
using vvll = vector<vector<long long int>>;
using ll = long long int;

int main(){
    ll N; cin >> N;
    vector<string> s(N);
    for(int i=0; i<N; i++){
        cin >> s[i];
    }
    ll c = 0;
    ll a = 0;
    ll b = 0;
    for(int i=0; i<N; i++){
        ll l = s[i].size();
        for(int j=0; j<l-1; j++){
            if(s[i][j] == 'A'&&s[i][j+1] == 'B'){
                c++;
            }
        }
        if(s[i][0] == 'B'){
            b++;
        }
        if(s[i][l-1] == 'A'){
            a++;
        }
    }
    c += min(a, b);
    cout << c;
}