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<cstring>
#include<cstdio>
using namespace std;
const int N=1005;
char s[15];
int n,a,b,c,ans;
int main(){
	scanf("%d",&n);
	for(int i=1;i<=n;++i){
		scanf("%s",s+1);
		int m=strlen(s+1);
		for(int j=1;j<m;++j)
			if(s[j]=='A'&&s[j+1]=='B') ans++;
		if(s[1]=='B'&&s[m]=='A') c++;
		else if(s[1]=='B') a++;
		else if(s[m]=='A') b++;
	}
	ans+=min(a,b);
	a-=min(a,b),b-=min(a,b);
	if(a<b) swap(a,b);
	ans+=min(a,c);
	c-=a;
	if(c>0) ans+=c/2;
	printf("%d",ans);
	return 0;
}