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 <vector>
#include <string>
#include <math.h>
#include <algorithm>
#include <map>
using namespace std;

int main()
{
	int n;
	cin >> n;
	int c = 0;
	int pa = 0, pb = 0;
	int c2 = 0;
	for (int i = 0; i < n; i++)
	{
		string s;
		cin >> s;
		for (int j = 0; j < s.length() - 1; j++)
			if (s[j] == 'A' && s[j + 1] == 'B')
				c++;
		
		if(s[0]=='B' && s[s.length()-1]=='A')
		{
			pb++; pa++; c2++;
		}
		else if(s[0]=='B')
		{
			pb++; c2++;
		}
		else if (s[s.length()-1] == 'A')
		{
			pa++; c2++;
		}
	}

	int p = min(pa, pb);
	if (p == c2)
		p--;
	cout << c + p << endl;
	//system("pause");
	return 0;
}