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())
	S = [""]*N
	ans = 0
	a_end = 0
	b_begin = 0
	a_end_b_begin = 0
	for i in range(N):
		S[i] = input()
		if "AB" in S[i]:
			ans += S[i].count("AB")
		if S[i][0] == "B":
			if S[i][-1] == "A":
				a_end_b_begin += 1
				continue
			b_begin += 1
		if S[i][-1] == "A":
			a_end += 1
	ans += min(b_begin, a_end)
	if b_begin > 0 or a_end > 0:
		ans += a_end_b_begin
	else:
		ans += a_end_b_begin-1

	print(ans)


if __name__ == '__main__':
	main()