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)

function Main(s) {
  var s = s.split("\n")[0].split(" ").map(e => parseInt(e, 10)).sort((a, b) => b - a);
  var cnt = 0;
  if ((s[1] - s[2]) % 2 === 0) {
    cnt += s[0] - s[1];
    s[2] += cnt;
    cnt += (s[0] - s[2]) / 2;
  } else {
    s[0]++;
    s[1]++;
    cnt++;
    cnt += s[0] - s[1];
    s[2] += s[0] - s[1];
    cnt += (s[0] - s[2]) / 2;
  }
  console.log(cnt);
}

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