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.chomp.to_i
ss = (0...n).map { gets.chomp }

ab = ss.map { |s| s.scan('AB').length }.inject(&:+)
xa = ss.select { |s| s[0] != 'B' && s[-1] == 'A' }.length
ba = ss.select { |s| s[0] == 'B' && s[-1] == 'A' }.length
bx = ss.select { |s| s[0] == 'B' && s[-1] != 'A' }.length

if xa == 0 && bx == 0
  if ba == 0
    puts(ab)
  else
    puts(ab + ba - 1)
  end
else
  puts(ab + ba + [xa, bx].min)
end