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>
using namespace std;
int main() {
  int N; cin>>N;
  int a=0,b=0,c=0,d=0;
  int ans=0;
  string s;
  for(int i=0;i<N;i++){
    cin>>s;
    if(s.at(s.size()-1)=='A') a++;
    if(s.at(0)=='B') b++;
    if(s.at(s.size()-1)=='A' && s.at(0)=='B') c++;
    for(int j=0;j<s.size()-1;j++)
      if(s.at(j)=='A' && s.at(j+1)=='B') d++;
  }
  a-=c;b-=c;
  if(a==0&&b==0) ans=c+d-1;
  else if((a!=0&&b==0) or (a==0&&b!=0)) ans=c+d;
  else ans=c+d+min(a,b);
  cout<<ans<<endl;
}