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>
int min(int a,int b){
    if(a<b) return a;
    return b;
}
int max(int a,int b){
    if(a>b) return a;
    return b;
}
int main(void){
    int n;
    char s[10000][15]={0};
    int i,j;
    int cnt=0,first=0,last=0,b=0,sum=0;
    scanf("%d",&n);
    for(i=0;i<n;i++){
        scanf("%s",s[i]);
    }
    for(i=0;i<n;i++){
        j=0;
        while(s[i][j]){
            if(s[i][j]=='A'&&(s[i][j-1]=='B')) cnt++;
            j++;
        }
        if((s[i][j-1]=='A')&&s[i][0]=='B'){
            b++;
        }else if(s[i][j-1]=='A'){
            last++;
        }else if(s[i][0]=='B'){
            first++;
        }
    }
    sum=max(b-1,0);
    if(b!=0){
        sum+=min(first+1,last+1);
    }else{
        sum+=min(first,last);
    }
    printf("%d\n",cnt+sum);//cnt+sum);
    return 0;
}