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.Diagnostics;

namespace AtCoder
{
    class Program
    {
        private static string Read() { return Console.ReadLine(); }
        private static int ReadInt() { return int.Parse(Read()); }
        private static long ReadLong() { return long.Parse(Read()); }
        private static double ReadDouble() { return double.Parse(Read()); }
        private static int[] ReadInts() { return Array.ConvertAll(Read().Split(), int.Parse); }
        private static long[] ReadLongs() { return Array.ConvertAll(Read().Split(), long.Parse); }
        private static double[] ReadDoubles() { return Array.ConvertAll(Read().Split(), double.Parse); }

        static int Solve(int N, string[] S)
        {
            var a = new List<string>();
            int b = 0;
            int c = 0;
            foreach (string s in S)
            {
                for (int i = 0; i < s.Length - 1; ++i)
                {
                    if (s[i] == 'A' && s[i + 1] == 'B') { ++c; }
                }
                if (s.Last() == 'A') { a.Add(s); }
                if (s.First() == 'B') { ++b; }
            }
            if (a.All(s => s.First() == 'B') && a.Count == b)
            {
                return c + b - 1;
            }
            else
            {
                return c + Math.Min(a.Count, b);
            }
        }

        static void Main(string[] args)
        {
            int N = ReadInt();
            var S = new string[N];
            for (int n = 0; n < N; ++n) { S[n] = Read(); }
            Console.WriteLine(Solve(N, S));
        }
    }
}