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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int ans = 0;
		int enda = 0, startb = 0, startbenda = 0;
		for(int i = 0; i < N; i++) {
			char[] s = sc.next().toCharArray();
			for(int j = 0; j < s.length-1; j++) {
				if(s[j] == 'A' && s[j+1] == 'B')
					ans++;
			}
			if(s[0] == 'B' && s[s.length-1] == 'A')
				startbenda++;
			if(s[0] == 'B')
				startb++;
			if(s[s.length-1] == 'A')
				enda++;			
		}
		ans += Math.min(enda, startb);
		if(enda == startbenda && startb == startbenda && startbenda != 0)
			ans--;
		System.out.println(ans);

	}

}