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 = [input() for _ in range(n)]
t = []
res = 0
for c in s:
    t.append(c[0] + c[-1])
    res += c.count('AB')

a,b,ba = 0,0,0
for c in t:
    if c == 'BA':
        ba += 1
    elif c[0] == 'B':
        b += 1
    elif c[-1] == 'A':
        a += 1

if ba > 0:
    res += ba - 1
    if a > 0:
        res += 1
        a -= 1
    if b > 0:
        res += 1
        b -= 1

res += min(a, b)

print(res)