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())
s = [input().strip() for _ in range(N)]



def main(s):
    SB = [si for si in s if si[0] == 'B']
    SR = [si for si in s if si[0] != 'B']
    if SR:
        R = [SR.pop()]
    else:
        R = [SB.pop()]
    while SR or SB:
        if SR and SB:
            if R[-1][-1] == 'A':
                R.append(SB.pop())
            else:
                R.append(SR.pop())
        elif SR:
            R.append(SR.pop())
        elif SB:
            R.append(SB.pop())
    return "".join(R).count("AB")


print(main(s))