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 JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

'use strict'
function Main(input){
  input=input.trim().split(/\s+/);
  var N=input.shift()-0;
  var rightA=input.reduce((acc,str)=>acc+(str[str.length-1]==='A'?1:0), 0);
  var leftB=input.reduce((acc,str)=>acc+(str[0]==='B'?1:0), 0);
  var AB=input.reduce((acc,str)=>acc+str.split('AB').length-1, 0);
  console.log(AB+Math.min(rightA,leftB,N-1));
}

Main(require('fs').readFileSync('/dev/stdin','utf8'));