Problem:
Score : 100 points

Problem Statement

We have two integers: A and B.

Print the largest number among A + B, A - B, and A \times B.

Constraints

All values in input are integers.

-100 \leq A,\ B \leq 100

Input

Input is given from Standard Input in the following format:

A B

Output

Print the largest number among A + B, A - B, and A \times B.

Sample Input 1

-13 3

Sample Output 1

-10

The largest number among A + B = -10, A - B = -16, and A \times B = -39 is -10.

Sample Input 2

1 -33

Sample Output 2

34

The largest number among A + B = -32, A - B = 34, and A \times B = -33 is 34.

Sample Input 3

13 3

Sample Output 3

39

The largest number among A + B = 16, A - B = 10, and A \times B = 39 is 39.

Solution in Ruby (2.3.3) (judge verdict: Wrong Answer)

def factorial(number)
  if number.zero?
    1
  else
    number * factorial(number - 1)
  end
end

N = gets
N.strip!
map = Hash.new
map.default = 0
begin
N.to_i.times do 
  s = gets
  map[s.strip.chars.sort.join] += 1
end
ans = 0

  map.each_value{|v|
    if v >= 2 then
      ans += factorial(v)/factorial(v-2)/2
    end
  }
rescue
  p 0
end
p ans