Problem:
Score : 300 points

Problem Statement

You are given three integers A, B and C. Find the minimum number of operations required to make A, B and C all equal by repeatedly performing the following two kinds of operations in any order:

Choose two among A, B and C, then increase both by 1.

Choose one among A, B and C, then increase it by 2.

It can be proved that we can always make A, B and C all equal by repeatedly performing these operations.

Constraints

0 \leq A,B,C \leq 50

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B C

Output

Print the minimum number of operations required to make A, B and C all equal.

Sample Input 1

2 5 4

Sample Output 1

2

We can make A, B and C all equal by the following operations:

Increase A and C by 1. Now, A, B, C are 3, 5, 5, respectively.

Increase A by 2. Now, A, B, C are 5, 5, 5, respectively.

Sample Input 2

2 6 3

Sample Output 2

5

Sample Input 3

31 41 5

Sample Output 3

23

Solution in Rust (1.42.0) (judge verdict: Accepted)

use proconio::{input, fastout};
use proconio::marker::{Chars};
use proconio::marker::Usize1;
use std::cmp::*;

macro_rules! debug {
      ($($a:expr),*) => {
          eprintln!(concat!($(stringify!($a), " = {:?}, "),*), $($a),*);
    }
}

#[fastout]
fn main() {
    input!{
        a: usize,
        b: usize,
        c: usize,
    }

    let mut l = max(max(a,b),c);
    let mut s = min(min(a,b),c);
    let mut m = 0;
    if (a>=b && a<=c) || (a>=c && a<=b) {
        m = a;
    } else if (b>=a && b<=c) || (b>=c && b<=a) {
        m = b;
    } else if (c>=a && c<=b) || (c>=b && c<=a){
        m = c;
    }

    let mut cnt = 0;
    while m>=s+2 {
        s += 2;
        cnt += 1;
    }

    if m==s {
        cnt += l-m;
    } else {
        cnt += l-m+2;
    }

    println!("{}", cnt);

}