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: Accepted)

<?php
$n = (int)trim(fgets(STDIN));

$base = 0;
$last_a = 0;
$first_b = 0;
$ba = 0;
for ($i=0; $i < $n; $i++) { 
	$s = trim(fgets(STDIN));
	$base += substr_count($s, 'AB');
	$b_flg = $a_flg = false;
	if ($s[0] === 'B') {
		$first_b += 1;
		$b_flg = true;
	}
	if ($s[strlen($s)-1] === 'A') {
		$last_a += 1;
		$a_flg = true;
	}
	if ($a_flg && $b_flg) {
		$ba += 1;
	}
}
if ($last_a === $first_b && $last_a === $ba) {
	$comb_cnt = max(0, $last_a - 1);
}else{
	$comb_cnt = min($last_a, $first_b);
}

echo $base + $comb_cnt;