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 PHP7 (7.0.15) (judge verdict: Wrong Answer)

<?php
$n=trim(fgets(STDIN));
$i=0;
$ans=0;
while($i<$n){
  $s=str_split(trim(fgets(STDIN)));
  $c=count($s);
  if($s[0]=="B"){
    $startB[]=$i+1;
  }
  $check=array_keys($s,"A");
  foreach($check as $v){
    if($v+1==$c){
      $endA[]=$i+1;
    }elseif($s[$v+1]=="B"){
      ++$ans;
    }
  }
  ++$i;
}
if(isset($endA)&&isset($startB)){
  $ba=0;
  foreach($endA as $v){
    if(in_array($v,$startB)){
      ++$ba;
    }
  }
  $addAB=min(count($endA),count($startB));
  $rAB=max(count($endA),count($startB));
  if($rAB-$addAB>0){
    $ans+=$addAB;
  }else{
    $ans+=$addAB-min($ba,1);
  }
}
echo $ans;