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
  s.push(gets.chomp)
end
ed_a=0
ft_b=0
ryouhou=0
count=0
for i in 0..n-1 do
  slen=s[i].length
  ft=s[i][0]
  ed=s[i][slen-1]
  if ed=="A" && ft=="B"
    ryouhou+=1
  elsif ed=="A"
    ed_a+=1
  elsif ft=="B"
    ft_b+=1
  end
  for cha in 0..slen-2
    count+=1 if s[i][cha]=="A" && s[i][cha+1]=="B"
  end
end
sa=(ed_a-ft_b).abs
tasu=0
if ryouhou==0
  tasu=ed_a>ft_b ? ft_b : ed_a
else
  if ed_a>0 || ft_b>0
    tasu=ryouhou+(ed_a>ft_b ? ft_b : ed_a)
  else
    tasu=ryouhou-1
  end
end

puts count+tasu