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
strings = []
n.times do
  strings.push(gets.chomp.to_s)
end

ab_count = 0
first_b_count = 0
last_a_count = 0
double_count = 0

strings.each do |string|
  ab_count += string.scan("AB").length
  if string[0] == "B" 
    first_b_count += 1
  end
  if string[string.length - 1] == "A"
    last_a_count += 1
  end
  if string[0] == "B" && string[string.length - 1] == "A"
    double_count += 1
  end
end

mixed_ab = [first_b_count, last_a_count].min

if first_b_count == last_a_count && last_a_count == double_count && double_count > 0
  mixed_ab -= 1
end

sum = ab_count + mixed_ab

puts sum