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 = n.times.map{gets.chomp}
ans = 0
b = 0 
a = 0
ba = 0
ss.each do |s|
  (0..s.size-1).each do|i|
    if s.slice(i,2) == "AB"
      ans += 1
    end
  end
  if s[0] == "B" && s[-1] == "A"
    ba += 1
  elsif s[0] == "B"
    b += 1
  elsif s[-1] == "A"
    a += 1
  end
end
ans += [a,b].min + [ba-1,0].max
if (a-b).abs > 0 && ba > 0
  ans += 1
end
puts ans