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;

namespace AtCoderDiverta2019C
{
    class Program
    {
        static void Main(string[] args)
        {
            int ans = 0;

            int N = int.Parse(Console.ReadLine());

            int EndA = 0;
            int StartB = 0;

            for (int i = 0; i < N; i++)
            {
                string s = Console.ReadLine();
                ans += (s.Length - s.Replace("AB", "").Length) / 2;

                if (s.StartsWith("B"))
                    StartB++;
                if (s.EndsWith("A"))
                    EndA++;
            }

            if (EndA == StartB)
                ans += EndA - 1;
            else if (EndA > StartB)
                ans += StartB;
            else
                ans += EndA;

            Console.WriteLine(ans.ToString());
        }
    }
}