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: Wrong Answer)

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int ans = 0;
		int start_with_B = 0;
		int end_with_A = 0;
		int B_any_A = 0;
		for(int i=0;i<n;i++) {
			String s = in.next();
			for(int j=0;j<s.length()-1;j++) {
				if(s.substring(j, j+2).equals("AB")) ans++;
			}
			if(s.charAt(0)=='B') start_with_B++;
			if(s.charAt(s.length()-1)=='A') end_with_A++;
			if(s.charAt(0)=='B' && s.charAt(s.length()-1)=='A') B_any_A++;
		}
		ans += Math.min(end_with_A, start_with_B);
		if(Math.max(end_with_A, start_with_B)==B_any_A) ans--;
		System.out.println(ans);
		in.close();
	}

}