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)

namespace diverta2019.C
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using static System.Console;


    public class Program
    {
        public static void Main(string[] args)
        {
            var n = int.Parse(ReadLine());

            var list = new List<string>();
            for (int i = 0; i < n; i++)
            {
                list.Add(ReadLine());
            }

            WriteLine(Solve(list));
        }

        public static int Solve(List<string> list)
        {

            var internalCount = FindInternal(list);

            var firstB = list.Where(x => x[0] == 'B').Count();
            var endA = list.Where(x => x.Last() == 'A').Count();

            var combined = System.Math.Min(firstB, endA);

            if (combined == list.Where(x => x[0] == 'B' && x.Last() == 'A').Count()) combined--;

            return internalCount + combined;
        }

        public static int FindInternal(List<string> list)
        {
            var internalCount = 0;
            var place = 0;

            foreach (var item in list)
            {
                place = 0;
                while (true)
                {
                    place = item.IndexOf("AB", place);
                    if (place < 0) break;

                    place += 1;
                    internalCount++;

                }
            }

            return internalCount;
        }
    }
}