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<iostream>
#include<iomanip>
//#include<cstdio>
#include<vector>
#include<map>
#include<queue>
#include<algorithm>
#include<cmath>
#include<cassert>
using namespace std;
typedef long long ll;

int main(){
    int N;
    int ba=0, xa=0, bx=0;
    int ans = 0;
    cin >> N;
    for(int i=0; i<N; i++){
        string s;
        cin >> s;
        if(s[0] == 'B' && s[s.size()-1] == 'A') ba++;
        else if(s[0] == 'B') bx++;
        else if(s[s.size()-1] == 'A') xa++;
        if(s.find("AB") != string::npos) ans++;
    }

    if(ba > 1) {
        ans += ba-1;
        xa++;
        bx++;
    } else if(ba==1){
        xa++;
        bx++;
    }
    ans += min(xa, bx);

    cout <<  ans << endl;

	return 0;
}