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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;

public class Prog
{
    public static void Main()
    {
        int N = int.Parse(Console.ReadLine());
        string[] S = new string[N];
        int AB = 0;
        int And = 0;
        int B = 0;
        int A = 0;
        for(int i = 0; i < N; i++)
        {
            S[i] = Console.ReadLine();
            if(S[i][0] == 'B')
            {
                B++;
            }
            if(S[i].Last() == 'A')
            {
                A++;
            }
            if(S[i][0] == 'B' && S[i].Last() == 'A')
            {
                And++;
            }
            int ind = S[i].IndexOf('A');
            while(ind != -1 && ind != S[i].Length-1)
            {
                if(S[i][ind+1] == 'B')
                {
                    AB++;
                }
                ind = S[i].IndexOf('A', ind+1);
            }
        }
        if(A == B && And == A)
        {
            Console.WriteLine(AB + A - 1);
        }
        else
        {
            Console.WriteLine(AB + Math.Min(A, B));
        }
    }
}