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)

#![allow(unused_imports)]
use proconio::input;
use proconio::marker::*;
use std::collections::HashSet;

fn main() {
  input! {
    a: usize,
    b: usize,
    c: usize,
  }
  
  let mut memo = vec![a,b,c];
  memo.sort();
  let a = memo[0];
  let b = memo[1];
  let c = memo[2];
  
  let cb = (c - b) % 2;
  let ca = (c - a) % 2;
  
  if cb == 0 && ca == 0 {
    println!("{}", (c - b) / 2 + (c - a) / 2);
  } else if (cb == 1 && ca == 0) || cb == 0 && ca == 1 {
    let v = (b - (a + 1)) / 2;
    let vv = c + 1 - b;
    println!("{}", 1 + v + vv);
  } else {
    println!("{}", 1 + ((c - b) / 2) + ((c - a) / 2));
  }
}