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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        int[] abc = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();
        int a = abc[0];
        int b = abc[1];
        int c = abc[2];
        int ans = 0;

        while(!(abc[0] == abc[1] && abc[1] == abc[2]))
        {
            Array.Sort(abc);
            if(abc[0] < abc[1])
            {
                abc[0] += 2;
            }else if(abc[0] == abc[1])
            {
                abc[0] += 1;
                abc[1] += 1;
            }
            ans++;
        }
        Console.WriteLine(ans);
    }
}