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<iostream>
using namespace std;
#include<vector>
#define int long long int
int32_t main()
{
     int n;
     cin>>n;
     int answer=0;
     int a=0,b=0,c=0;
     vector<string> v1,v2;
     for(int j=0;j<n;j++)
     {
		 string str;
		 cin>>str;
		 int l=str.size();
		 int i;
		 for(i=0;i<l-1;i++)
		 {
			 if(str[i]=='A'&&str[i+1]=='B')
			    answer++;
		 }
		 if(str[l-1]=='A'&&str[0]!='B')
		 {
			a++;
		 }
		 if(str[0]=='B'&&str[l-1]!='A')
		 {
			 b++;
		 }
		 if(str[0]=='B'&&str[l-1]=='A')
		 {
			 c++;
		 }
	 }
     if(c==0)
     {
		 answer+=min(a,b);
	 }
	 else
	 {
		 if(a+b>0)
		 {
			 answer+=min(a,b)+c;
		 }
		 else
		 {
			 answer+=c-1;
		 }
	 }
	 cout<<answer<<endl;
}