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())
c=0
ica = [0]*n
icb = [0]*n

for i in range(n):
    a = input().split()
    c += a[0].count('AB')
    if a[0][-1:] == 'A':
        ica[i] = 1
    if a[0][:1] == 'B':
        icb[i] = 1


cc = [1]*n
for i in range(n):
    if ica[i] == 1 and icb[i] == 0:
        cc[i] = 0
        break

e=0
s=0
o=0
for i in range(n):
    s=0
    if o == 0:
        for j in range(n):
            if ica[j] == 1 and icb[j] == 1 and cc[j] == 1:
                cc[j] = 0
                c+=1
                s=1
                break
    if s==0 and e==0:
        o=1
        for j in range(n):
            if icb[j] == 1 and cc[j] == 1:
                s=1
                e=1
                c+=1
                cc[j]=0
                break
    if s==0 and e==1:
        o=1
        for j in range(n):
            if ica[j] == 1 and cc[j] == 1:
                e=0
                s=1
                cc[j]=0
                break
    if s==0:
        break

print(c)