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

count = 0
begin_b_count = 0
end_a_count = 0
begin_b_end_a_count = 0
n.times do
  str = gets.chomp
  count += str.scan(/AB/).size
  begin_b_count += 1 if str[0] == 'B'
  end_a_count += 1 if str[-1] == 'A'
  begin_b_end_a_count += 1 if str[0] == 'B' && str[-1] == 'A'
end

if end_a_count > 0 && end_a_count == begin_b_count && end_a_count == begin_b_end_a_count
  count -= 1
end

puts count + [begin_b_count, end_a_count].min