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
ss=$<.read.split.map(&:chomp)

a = 0
b=0
ab=0
ret = 0
ss.each do |s|
  i = -1
  ret += 1 while i = s.index('AB',i+1)
  if s[0]=='B' && s[-1]=='A'
    ab+=1
  elsif s[0]=='B'
    b+=1
  elsif s[-1]=='A'
    a+=1
  end
end

if 0 < ab
  ret += ab-1
  if 0 < a
    a -= 1
    ret += 1
  end
  if 0 < b
    b -= 1
    ret += 1
  end
end

ret += [a,b].min
puts ret