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 Python (3.4.3) (judge verdict: Wrong Answer)

N = int(input())

ends_with_A = 0
starts_with_B = 0
both = 0

count = 0

for _ in range(N):
  s = input()
  count += s.count('AB')
  if s.endswith('A') and s.startswith('B'):
    both += 1
  elif s.endswith('A'):
    ends_with_A += 1
  elif s.startswith('B'):
    starts_with_B += 1

# 結合した文字が AXXXXXX or XXXXXXXB となるとき     
if ends_with_A != starts_with_B:
  print(count + both + min(ends_with_A, starts_with_B))
else:  
  print(
    max(
      count + both + min(ends_with_A, starts_with_B) - 1,
      0
    )
  )