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 {

    void run() {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int aEndCount = 0;
        int bStartCount = 0;
        int aEndBStartCount = 0;
        int abInnerCount = 0;


        for (int i = 0; i < n; i++) {
            String s = sc.next();

            if (s.charAt(0) == 'B' && s.charAt(s.length() - 1) == 'A') aEndBStartCount++;
            else if (s.charAt(0) == 'B') bStartCount++;
            else if (s.charAt(s.length() - 1) == 'A') aEndCount++;

            for (int j = 0; j < s.length() - 1; j++) {
                if (s.substring(j, j + 2).equals("AB")) abInnerCount++;
            }
        }

//        System.out.println(aEndCount);
//        System.out.println(bStartCount);
//        System.out.println(aEndBStartCount);
//        System.out.println(abInnerCount);
//        System.out.println("-------");
        if (aEndBStartCount > 0) {
            if (aEndCount != bStartCount) {
                aEndBStartCount++;
            }
            aEndBStartCount--;
        }

        int concatCount = Math.min(aEndCount, bStartCount) + aEndBStartCount;
//        System.out.println(concatCount);
//        System.out.println(abInnerCount);

        // write your code
        System.out.println(abInnerCount + concatCount);
    }

    void debug(Object... os) {
        System.err.println(Arrays.deepToString(os));
    }

    public static void main(String[] args) {
        new Main().run();
    }
}