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;
using System.Text;
using System.Threading.Tasks;

namespace Diverta
{
    class C
    {
        static void Main(string[] args)
        {
            int N = int.Parse(Console.ReadLine());

            int countA = 0, countB = 0, countAB = 0;
            for (int i = 0; i < N; i++)
            {
                string s = Console.ReadLine();
                if (s[0] == 'B') countB++;
                if (s[s.Length - 1] == 'A') countA++;
                while (s.Length > 0)
                {
                    int id = s.IndexOf("AB");
                    if (id >= 0)
                    {
                        countAB++;
                        s = s.Substring(id + 2);
                    }
                    else
                    {
                        break;
                    }
                }
            }
            int max = countAB + Math.Min(countA, countB);
            Console.WriteLine(max);
        }

    }
}