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)

  def get_i
    gets.to_i
  end

  def get_ia(delimiter = ' ')
    gets.split(delimiter).map(&:to_i)
  end
    n = get_i
    c = 0
    bb = 0
    ea = 0
    bo = 0
    for i in 1..n
      t = gets.chomp.gsub("AB", "-")
      c += t.count("-")
      b = 0
      if t[0] == "B"
        bb += 1
        b += 1
      end
      if t[-1] == "A"
        ea += 1
        b += 1
      end
      if b == 2
        bo += 1
      end
    end
    a = [ea, bb].min
    if ea == bo && bb == bo
      c += [a - 1, 0].max
    else
      c += a
    end
    puts c