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: Accepted)

N = gets.to_i

a = 0
b = 0
ab = 0
res = 0

N.times do
  s = gets.chomp
  if s[0] == 'B' && s[-1] == 'A'
    ab += 1
  elsif s[0] == 'B'
    b += 1
  elsif s[-1] == 'A'
    a += 1
  end
  (0...(s.length)).each do |i|
    if s.slice(i, 2) == 'AB'
      res += 1
    end
  end
end


if a > 0
  while a > 0 do
    a -= 1
    res += ab
    ab = 0

    if b > 0
      b -= 1
      res += 1
    end
  end
else
  if ab >= 2
    res += ab-1
    if b > 0
      res += 1
    end
  elsif ab >= 1
    if b > 0
      res += 1
    end
  end
end

puts res