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 sc = new Scanner(System.in);
		int N = sc.nextInt();
		// 空振り用
		sc.nextLine();
		int abCount = 0;
		int startWithBCount = 0;
		int endWithACount = 0;
		int btoaCount = 0;
		for (int i = 0; i < N; i++) {
			String str = sc.nextLine();
			if (str.charAt(0) == 'B') {
				startWithBCount++;
				if (str.endsWith("A")) {
					btoaCount++;
				}
			}
			if (str.endsWith("A")) {
				endWithACount++;
			}
			int initLength = str.length();
			String trimStr = str.replaceAll("AB", "");
			abCount += (initLength - trimStr.length()) / 2;
		}
		sc.close();
		int ba = Math.min(startWithBCount, endWithACount);
		int baMax = Math.max(startWithBCount, endWithACount);
		if (btoaCount == baMax) {
			ba--;
		}
		System.out.println(abCount + ba);
	}
}