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: Accepted)

n = int(input())
s = []
for i in range(n):
    s.append(str(input()))

Bset = set()
Aset = set()
ans = 0
for i in range(n):
    if s[i][0] == "B":
        Bset.add(i)
    if s[i][-1] == "A":
        Aset.add(i)
    for j in range(1, len(s[i])):
        if s[i][j - 1] == "A" and s[i][j] == "B":
            ans += 1

Bli = list(Bset)
Ali = list(Aset)
ans += min(len(Bli), len(Ali))
if Bset == Aset and Bset != set():
    ans -= 1
print(ans)