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 foreach(i, v) for(__typeof((v).begin()) i = (v).begin(); i != (v).end(); ++ i)
#define BETWEEN(a, x, b) (a<=x&&x<b)

using namespace std;
typedef long long ll;

int main(int argc, char *argv[]) {
  ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);

  int n;cin>>n;
  int a=0;
  int b=0;
  int ba=0;
  int res=0;
  for(int i=0;i<n;i++){
    string s;cin>>s;
    for(int j=0;j<s.size()-1;j++){
      if(s[j]=='A'&&s[j+1]=='B')res++;
    }
    if(s[0]=='B')b++;
    if(s[s.size()-1]=='A')a++;
    if(s[0]=='B'&&s[s.size()-1]=='A')ba++;
  }

  res+=min(b,a);
  if(b==a&&ba==b)res--;

  cout<<res<<endl;

  return 0;
}