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

public static partial class Program
{
    //テンプレここから
    public static int ToInt(this string str)
    {
        return int.Parse(str);
    }

    public static long ToLong(this string str)
    {
        return long.Parse(str);
    }
    public static IEnumerable<int> ToInt(this string[] strs)
    {
        return strs.Select(x => x.ToInt());
    }

    public static IEnumerable<long> ToLong(this string[] strs)
    {
        return strs.Select(x => x.ToLong());
    }
    public static IEnumerable<int> SplToInt(this string str, char opr = ' ')
    {
        return str.Split(opr).ToInt();
    }

    public static IEnumerable<long> SplToLong(this string str, char opr = ' ')
    {
        return str.Split(opr).ToLong();
    }
    public static string CRL()
    {
        return Console.ReadLine();
    }
    public static void CWL(object obj)
    {
        Console.WriteLine(obj);
    }
    public static int Diff(int a, int b)
    {
        return Math.Abs(Math.Max(a, b) - Math.Min(a, b));
    }
    public static long Diff(long a, long b)
    {
        return Math.Abs(Math.Max(a, b) - Math.Min(a, b));
    }
    public static int Sign(this int i)
    {
        return Math.Sign(i);
    }

    public static bool IsEven(this int i)
    {
        return i % 2 == 0;
    }
    //テンプレここまで
}

public static partial class Program
{
    static void Main()
    {
        var abc = CRL().SplToInt().ToArray();
        var max = abc.Max();

        if (max.IsEven() != abc.Sum().IsEven())
        {
            max++;
        }

        var count = 0;
        foreach (var i in abc)
        {
            count += max - i;
        }

        CWL(count / 2);
    }
}