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)

# -*- coding: utf-8 -*-
N = int(input())
S = []
for i in range(N):
    S.append(str(input()))
    
start_b = 0
end_a = 0
both = 0
ab_count = 0
for i in S:
    if i[0]=="B":
        start_b = start_b + 1
    if i[-1]=="A":
        end_a = end_a + 1
    if i[0]=="B" and i[-1]=="A":
        both = both + 1
    ab_count = ab_count + i.count("AB")

additional = min(start_b, end_a)
if additional == both:
    additional = additional  - 1
ans = ab_count + additional
print(ans)