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.*;
public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.parseInt(sc.next());
		String s[] = new String[N];
		int a_num = 0;
		int b_num = 0;
		boolean flag = true;
		int ans = 0;
		for(int i = 0; i < N; i++) {
			s[i] = sc.next();
			if(s[i].substring(0, 1).equals("B")) {
				b_num++;
			}
			if(s[i].substring(s[i].length() - 1, s[i].length()).equals("A")){
				a_num++;
			}
			if(s[i].substring(0, 1).equals("B") || s[i].substring(s[i].length() - 1, s[i].length()).equals("A")) {
				flag = false;
			}
			for(int j = 0; j < s[i].length() - 1; j++) {
				if(s[i].substring(j, j + 2).equals("AB")) ans++;
			}
		}
		ans += Math.min(a_num, b_num);
		if(Math.min(a_num, b_num) != 0 && flag) {
			ans--;
		}
		System.out.println(ans);
	}
}