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

a_flag_count = 0
b_flag_count = 0
a_b_flag_count = 0
count = 0
n.times do |t|
  str = gets.chomp
  count += str.scan(/AB/).size
  a_flag = str[-1] == "A"
  b_flag = str[0] == "B"
  if a_flag && b_flag then
    a_b_flag_count += 1
  elsif a_flag then
    a_flag_count += 1
  elsif b_flag then
    b_flag_count += 1
  end
end

if a_b_flag_count > 0 then
  count += (a_b_flag_count - 1)
  if a_flag_count > 0 then
    count += 1
    a_flag_count -= 1
  end
  if b_flag_count > 0 then
    count += 1
    b_flag_count -= 1
  end
  count += [a_flag_count, b_flag_count].min
else
  count += [a_flag_count, b_flag_count].min
end

puts count