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: Accepted)

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
#define loop(i,L,R) for(int i=(L);i<=(R);i++)
const int maxn=1e5+5;
int main()
{
    int n;
    string s;
    scanf("%d",&n);
    int ans=0,x=0,y=0,z=0;
    rep(i,n)
    {
        cin>>s;
        int n=s.size();
        rep(i,n-1) if(s[i]=='A'&&s[i+1]=='B') ans++;
        if(s[0]=='B') x++;
        if(s[n-1]=='A') y++;
        if(s[0]=='B'&&s[n-1]=='A') z++;
    }
    if(x==y&&x==z&&x&&y&&z) ans+=(x-1);
    else ans+=min(x,y);
    printf("%d\n",ans);
}