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<cstdio>
#include<cstring>
char s[15];
bool used[10005];
int main(){
	int n,i,j,l,ans=0,sa=0,sb=0;
	bool flag=0,ok=0;
	scanf("%d",&n);
	for(i=0;i<n;++i){
		scanf("%s",s);
		l=strlen(s);
		for(j=0;j<l-1;++j)if(s[j]=='A'&&s[j+1]=='B')++ans;
		if(s[l-1]=='A')++sa;
		if(s[0]=='B')++sb;
		if(s[l-1]=='A'&&s[0]=='B')flag=1;
		else if(s[l-1]=='A'||s[0]=='B')ok=1;
	}
	ans+=sa<sb?sa:sb;
	if(sa==sb&&flag&&!ok)--ans;
	printf("%d\n",ans);
	return 0;
}