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 Cmondai
{
    static void Main()
    {
        var abc = Console.ReadLine().Split(' ').Select(num => Int32.Parse(num)).ToArray();
        var A = abc[0];
        var B = abc[1];
        var C = abc[2];
        var max = abc.Max();
        var tarinai = new List<int>();
        if (A != max) tarinai.Add(A);
        if (B != max) tarinai.Add(B);
        if (C != max) tarinai.Add(C);
        var ans = 0;
        for (int i=0;i<tarinai.Count();)
        {
            var sa = max - tarinai[i];
            if (1 < sa)
            {
                ans += sa / 2;
                tarinai[i] += (sa / 2) * 2;
                if (tarinai[i] == max) tarinai.RemoveAt(i);
                else i++;
            }
            else i++;
        }
        //二つ違う
        if (tarinai.Count()==2) ans++;
        //一つだけ違う
        else if (tarinai.Count()==1) ans += 2;
        Console.WriteLine(ans);
    }
}