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 Java (OpenJDK 11.0.6) (judge verdict: Accepted)

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int ans = 0;
        int a = 0;
        int b = 0;
        int ab = 0;
        for (int i=0;i<n;i++){
            String s = sc.next();
            if (s.charAt(0)=='B'){
                if (s.charAt(s.length()-1)=='A')ab++;
                else b++;
            }else {
                if (s.charAt(s.length()-1)=='A')a++;
            }
            for (int j=0;j<s.length()-1;j++){
                if (s.charAt(j)=='A'&&s.charAt(j+1)=='B')ans++;
            }
        }
        if (ab!=0){
            ans+=ab-1;
            if (a!=0){
                ans++;
                a--;
            }
            if (b!=0){
                ans++;
                b--;
            }
        }
        ans+=Math.min(a,b);
        System.out.println(ans);
    }
}