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 Ruby (2.3.3) (judge verdict: Accepted)

n = gets.chomp.to_i
tale_a = 0
head_b = 0
tale_a_and_head_b = 0
ans = 0
n.times do
    s = gets.chomp
    ans += s.scan("AB").length
    if s[-1] == "A" && s[0] == "B"
        tale_a_and_head_b += 1
    elsif s[-1] == "A"
        tale_a += 1
    elsif s[0] == "B"
        head_b += 1
    end
end

if tale_a_and_head_b == 0
    puts ans + [tale_a, head_b].min
else
    if tale_a + head_b > 0
        puts ans + tale_a_and_head_b + [tale_a, head_b].min
    else
        puts ans + tale_a_and_head_b - 1
    end
end