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 scn = new Scanner(System.in);
		int N = scn.nextInt();
		int ans = 0;
		int A = 0, B = 0;
		String[] str = new String[N];
		scn.nextLine();
		for(int i = 0;i < N;i++) {
			String buf = scn.nextLine();
			char[] ch = buf.toCharArray();
			boolean isA = false;
			for(int j = 0;j < ch.length;j++) {
				if(j == 0) {
					if(ch[j]=='B')B++;
				}
				if(j == ch.length-1) {
					if(ch[j] == 'A')A++;
				}
				if(isA) {
					if(ch[j]=='B') ans++;
				}

				if(ch[j]=='A') {
					isA = true;
				}else {
					isA = false;
				}
			}
		}
		ans+= Math.min(A, B);
		if(A==B && A==N)ans--;
		System.out.println(ans);

	}

}