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)

def main():
    n = int(input())
    ls = [input() for _ in range(n)]
    acount = 0
    bcount = 0
    abcount = 0
    bacount = 0
    for s in ls:
        abcount += s.count("AB")
        if s[0] =="B" and s[-1] =="A":bacount += 1
        elif s[0] =="B":bcount += 1
        elif s[-1] =="A":acount += 1

    if acount == 0 and bcount == 0:
        print(abcount+bacount-1)
    elif acount == 0 or bcount == 0:
        print(abcount+bacount)
    else:
        print(abcount+bacount+min(acount,bcount))

main()