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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <string.h>
#include <math.h>
int main (void){
        int N,a=0,b=0,c=0,d=0,ans=0;
        char S[20];
        scanf("%d\n",&N );
        for (int i = 0; i < N; i++) {
          scanf("%s",S);
          for (int i = 0; i < strlen(S)-1; i++) {
            if (S[i]=='A'&&S[i+1]=='B') {
              ans+=1;
            }
          }
          if (S[0]=='B'&&S[strlen(S)-1]=='A') {
            d++;
          }else if(S[strlen(S)-1]=='A'){
            b++;
          }else if (S[0]=='B'){
            c++;
          }else{
            a++;
          }
        }
        if (b>c) {
          ans+=c;
        }else{
          ans+=b;
        }
        ans+=d;
        if (b+c==0) {
          ans-=1;
        }
        printf("%d\n",ans );
        return 0;
}