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;
class Program
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());
            int a = 0, b = 0, ab = 0;
            bool allBXA = true;
            for (int i=0; i<n; i++)
            {
                string s = Console.ReadLine();
                if (s[0] == 'B')
                {
                    b++;
                    if (s[s.Length - 1] != 'A') allBXA = false;
                }
                if (s[s.Length - 1] == 'A')
                {
                    a++;
                    if (s[0] != 'B') allBXA = false;
                }
                for (int j=0; j < s.Length - 1; j++)
                {
                    if (s[j] == 'A' && s[j+1] == 'B') ab++;
                }
            }
            ab += Math.Min(a, b);
            if (allBXA) ab--;
            Console.WriteLine(ab);
            
        }
    }
    //mcs Main.cs
    //mono Main.exe