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: Accepted)

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,m,ac=0,bc=0,cc=0,ans=0;
    cin>>n;
    string s;
    for(int i=0;i<n;i++){
        cin>>s;
        m=s.size();
        if(s[0]=='B'&&s[m-1]=='A'){cc++;}
        else if(s[0]=='B'){bc++;}
        else if(s[m-1]=='A'){ac++;}
        
        
        for(int j=0;j<m-1;j++){
            if(s[j]=='A'&&s[j+1]=='B'){ans++;}
        }
    }
    if(cc==0){cout<<ans+min(ac,bc);return 0;}
    else if(bc+ac>0){cout<<ans+cc+min(ac,bc);return 0;}
    else{cout<<ans+cc-1;return 0;}
}