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())
ss = [input() for _ in range(N)]
cnt = 0
ba = 0
b = 0
a = 0
o = 0
import re
for s in ss:
    cnt += len(re.findall('AB', s))
    if s[-1] == 'A' and s[0] == 'B':
        ba += 1
    elif s[-1] == 'A':
        a += 1
    elif s[0] == 'B':
        b += 1
    else:
        o += 1

if ba > 0:
    if b > 0 and a > 0:
        cnt += ba + 1 + min(a-1, b-1)
    elif b == 0 and a == 0:
        cnt += ba - 1
    else:
        cnt += ba
else:
    cnt += min(a, b)

print(cnt)