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: Wrong Answer)

using System;
using System.Text.RegularExpressions;
using System.Numerics;

namespace ConsoleApp2
{
    class Program
    {
        static void Main(string[] args)
        {
            string str = Console.ReadLine(); //標準入力
            //string str = "2 6 3";
            string[] str2 = str.Split(' ');
            int[] src = new int[3];

            src[0] = int.Parse(str2[0].ToString());
            src[1] = int.Parse(str2[1].ToString());
            src[2] = int.Parse(str2[2].ToString());

            int index = 0;
            int[] tmp = new int[3];
            while(true)
            {
                if (src[0] == src[1] && src[1] == src[2])
                {
                    Console.WriteLine(index);
                    break;
                }

                Array.Copy(src, tmp, 3);
                Array.Sort(tmp);
                if (tmp[0] - tmp[1] >= 2 && tmp[1] != tmp[2])
                {
                    tmp[0] = tmp[0] + 2;
                }
                else
                {
                    tmp[0]++;
                    tmp[1]++;
                }
                src = tmp;
                index++;
            }
            Console.WriteLine(index);

        }
    }
}