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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
#include <vector>
#include <string>
using namespace std;

int main(){
  int N;
  cin >> N;
  string data;
  int counter = 0;
  int counter_A = 0;
  int counter_B = 0;

  for(int i = 0;i < N;i++){
    cin >> data;
    for(int j = 0;j < data.size();j++){
      if(data.substr(j,2) == "AB")counter++;
    }
    if(data.substr(data.size() - 1,1) == "A")counter_A++;
    if(data.substr(0,1) == "B")counter_B++;
  }
  
  int counter_AB = min(counter_A,counter_B);
  if(counter_AB == N)counter_AB -= 1;
  counter += counter_AB;
  cout << counter << endl;
}