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
s = []
n.times do |i|
  s[i] = gets.chomp
end

ans = 0
count_Bxxx = 0
count_xxxA = 0
count_BxxA = 0
n.times do |i|
  count_Bxxx += 1 if s[i][0] == 'B'
  count_xxxA += 1 if s[i][-1] == 'A'
  count_BxxA += 1 if s[i][0] == 'B' && s[i][-1] == 'A'
  ans += s[i].scan('AB').size
end

ans += [count_Bxxx, count_xxxA].min
ans -= 1 if (count_BxxA > 0) && (count_Bxxx == count_BxxA) && (count_xxxA == count_BxxA)

puts(ans)