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

end_with_a = 0
start_with_b = 0
intersection = 0
ans = 0

N.times do
 s = gets.chomp
 if s[0] == "B" && s[s.length-1] != "A"
   start_with_b += 1
 end

 if s[s.length-1] == "A" && s[0] != "B"
   end_with_a += 1
 end

 if s[0] == "B" && s[s.length-1] == "A"
   intersection += 1
 end


 0.upto(s.length-2) do |i|
   if s[i] == "A" && s[i+1] == "B"
     ans += 1
   end
 end
end
# puts ans
# puts start_with_b
# puts end_with_a
# puts intersection

ans += [intersection - 1, 0].max

if intersection >= 1
  if start_with_b >= 1
    ans += 1
    start_with_b -= 1
  end

  if end_with_a >= 1
    ans += 1
    end_with_a -= 1
  end
end

ans +=
  if start_with_b == 0 && end_with_a == 0
    0
  elsif start_with_b > end_with_a
    end_with_a
  else
    start_with_b
  end



puts ans