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 JavaScript (node.js v5.12) (judge verdict: Accepted)

'use strict'

function main(s) {
  
  s = s.split('\n')[0].split(' ').map(n => Number(n));
  const A = s[0];
  const B = s[1];
  const C = s[2];

  const abc_sum = A + B + C;
  let same_sum = Math.max(...[A, B, C]) * 3;

  if (abc_sum % 2 !== same_sum % 2) same_sum += 3;

  const answer = (same_sum - abc_sum) / 2;
  console.log(answer);
}

main(require("fs").readFileSync("/dev/stdin", "utf8"));