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>
#define ALL(v) v.begin(), v.end()
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define rep1(i, n) for(int i = 1; i <= (int)(n); i++)
using namespace std;
typedef long long ll;
 
int main(){
int n;
  cin>>n;
  
  int cnt=0;
  int ea=0;
  int be=0;
  int ba=0;
  for(int i=1;i<=n;i++){
    string s;
    cin>>s;
    for(int i=0;i<s.size()-1;i++){
      if(s[i]=='A'&&s[i+1]=='B'){
        cnt++;}
    }
  int n=s.size();
    if(s[0]=='B'&&s[n-1]!='A'){
      be++;}
    if(s[0]!='B'&&s[n-1]=='A'){
      ea++;}
    if(s[0]=='B'&&s[n-1]=='A'){
      ba++;}
  }
    
  if(max(ea,be)!=0){
   cnt+=ba+min(ea,be);}
  if(max(ea,be)==0){
    cnt+=ba-1;}
  
  cout<<cnt<<endl;

  
}