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)

import re

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

tmp = 0

B_A = 0
B_any = 0
any_A = 0

for i in range(N):
    tmp = tmp + s[i].count("AB")
    if s[i][0:1] == "B":
        if s[i][-1:] == "A":
            B_A = B_A + 1
        else:
            B_any = B_any + 1
    elif s[i][-1:] == "A":
        any_A = any_A + 1

add = 0

add1 = min(B_any,any_A)

add = max(B_A - 1,0)


if B_any != any_A:
    if B_A >= 1:
        add1 = add1 + 1

print(tmp+add+add1)