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 Ruby (2.3.3) (judge verdict: Wrong Answer)

n = gets.to_i
ss = []
ab_count = 0
la_count = 0
fb_count = 0
lafb_count = 0
n.times do
  s = gets.chomp
  (0..s.size-2).each do |i|
    if s[i..i+1] == 'AB'
      ab_count += 1
    end
  end
  if s[-1] == 'A' && s[0] == 'B'
    if la_count > fb_count
      fb_count += 1
    else
      la_count += 1
    end
  else
    la_count += 1 if s[-1] == 'A'
    fb_count += 1 if s[0] == 'B'
  end
end
puts ab_count + [la_count, fb_count].min