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)

require 'pp'
n = gets.to_i
b_str_a = []
str_a = []
b_str = []
str = []
cnt = 0
n.times do
  ss = gets.chomp
  ss.chars.each_cons(2).each do |(a,b)|
    cnt += 1 if a == "A" && b == "B"
  end
  ss = ss.gsub('AB', '**').gsub('[C-Z]', '*')
  if ss[0] == 'B' && ss[-1] == 'A'
    b_str_a << 'B*A'
  elsif ss[0] == 'B'
    b_str << 'B*'
  elsif ss[-1] == 'A'
    str_a << '*A'
  else

  end
end

# pp b_str_a
# pp str_a
# pp b_str
# p cnt

minab = [str_a.size, b_str.size].min
maxab = [str_a.size, b_str.size].max
restab = maxab - minab
cnt += minab

cnt += [restab, b_str_a.size].min
cnt += b_str_a.size - 1
p cnt

# 2 4 4