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())
c1=c2=c3=0
c=0
for i in range(n):
  s=input()
  c+=s.count('AB')

  if s[0]=='B' and s[-1]=='A':
    c3+=1
  elif s[0]=='B':
    c1+=1
  elif s[-1]=='A':
    c2+=1

cc=c
c11=c1
c22=c2
c33=c3
cc+=max(0,c33-1)
if c11<c22:
  c22-=c1
  cc+=c11
  if c22>0 and c33>0:
    cc+=1
elif c11==c22:
  cc+=c11
else:
  c11-=c22
  cc+=c22
  if c11>0 and c33>0:
    cc+=1

if c3>max(c1,c2):
  if c1<c2:
    c+=c1*2
    c3-=c1
    c+=c3
  elif c1==c2:
    c+=c1*2
    c3-=c1
    c+=max(0,c3-1)
  else:
    c+=c2*2
    c3-=c2
    c+=c3
elif c3>=min(c1,c2) and c3<=max(c1,c2):
  if c1<c2:
    c+=c1*2
    c2-=c1
    c3-=c1
    c+=c3
  else:
    c+=c2*2
    c1-=c2
    c3-=c2
    c+=c3
else:
  c+=c3*2
  c1-=c3
  c2-=c3
  c+=min(c1,c2)

print(max(c,cc))