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 ll long long 
#define pb push_back
#define mod 1000000007
#define all(v) v.begin(),v.end()
#define MP make_pair
#define F first
#define S second
#define sz(v) (ll)v.size()
#define inf 100000000000000
#define vll vector<ll>
#define pll pair<ll,ll>nnnn
using namespace std;
const int N=250;

void solve()
{
	ll ans,x=0,y=0,z=0,i,j,n,m;
	ans=0;
	string s;
	cin>>n;
	for(i=0;i<n;i++)
	{
		cin>>s;
		m=s.length();
		for(j=0;j<m-1;j++)
			if(s[j]=='A' && s[j+1]=='B')
				ans++;
		if(s[0]=='B' && s[m-1]=='A') z++;
		else if(s[0]=='B') y++;
		else if(s[m-1]=='A') x++;
	}
	ans+=(x+y+z)/2;
	cout<<ans;
}
int main() {
    
    ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	
    ll t=1;
    //cin>>t;
    while(t--)
        solve();
 
    
    return 0;
}