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) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner sc = new Scanner(System.in);
		int n = Integer.parseInt(sc.next());
		String[] s = new String[n];
		
		for(int i = 0; i < n; i++) {
			s[i] = sc.next();
		}
		sc.close();
		int a = 0;// ...A
		int b = 0;// B...
		int c = 0;// B...A
		int ans = 0;
		for(int i = 0; i < n; i++) {
			String first = String.valueOf(s[i].charAt(0));
			String end = String.valueOf(s[i].charAt(s[i].length()-1));
			for(int j = 0; j < s[i].length()-1; j++) {
				String ich = String.valueOf(s[i].charAt(j));
				String ni = String.valueOf(s[i].charAt(j+1));
				if (ich.equals("A") && ni.equals("B")) {
					ans++;
				}
			}
			if(first.equals("B") && end.equals("A")) {
				c++;
			} else if (first.equals("B")) {
				b++;
			} else if (end.equals("A")) {
				a++;
			}
		}
		if (c == 0) {
			ans += Math.min(a,b);
		} else if (a == 0 || b == 0) {
			ans += c;
		} else {
			ans += c+1 + Math.min(a-1,b-1);
		}
		System.out.println(ans);
	}

}