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 Rust (1.15.1) (judge verdict: Accepted)

use std::io::{BufRead, Read};

pub struct Scanner<R>
where
    R: BufRead,
{
    reader: R,
}

impl<R> Scanner<R>
where
    R: BufRead,
{
    pub fn new(reader: R) -> Self {
        Scanner { reader: reader }
    }

    pub fn next<T>(&mut self) -> T
    where
        T: ::std::str::FromStr,
        <T as ::std::str::FromStr>::Err: ::std::fmt::Debug,
    {
        self.reader
            .by_ref()
            .bytes()
            .map(|b| b.unwrap() as char)
            .skip_while(|c| c.is_whitespace())
            .take_while(|c| !c.is_whitespace())
            .collect::<String>()
            .parse::<T>()
            .unwrap()
    }
}

use std::cmp::max;

fn main() {
    let stdin = std::io::stdin();
    let stdin = stdin.lock();
    let mut sc = Scanner::new(stdin);

    let a: i32 = sc.next();
    let b: i32 = sc.next();

    println!("{}", max(max(a+b, a-b), a*b));
}