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: Time Limit Exceeded)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Practice
{
    class Program
    {
        static void Main(string[] args)
        {
            string szLine = Console.ReadLine();
            string[] szArr = szLine.Split(' ');
            int nTotal = szArr.Length;
            long[] arr = new long[nTotal];
            

            for (int i = 0; i < arr.Length; ++i)
            {
                arr[i] = long.Parse(szArr[i]);
            }

            long a = arr[0];
            long b = arr[1];
            long c = arr[2];
            bool[] target = new bool[arr.Length];
            // 同じ最大値が２個ならstep2
            // 全部バラはなstep1
            int procTotal = 0;
            while (true)
            {
                long max = Math.Max(a, Math.Max(b, c));
                int maxCount = 0;
                for (int i = 0; i < arr.Length; ++i)
                {
                    if (arr[i] == max)
                    {
                        maxCount++;
                        target[i] = false;
                    }
                    else
                    {
                        target[i] = true;
                    }
                }
                if (maxCount == 3)
                {
                    Console.WriteLine(procTotal);
                    break;
                }
                else if (maxCount == 2)
                {
                    procTotal++;
                    // 一個だけ2増やす
                    for (int i = 0; i < arr.Length; ++i)
                    {
                        if (target[i])
                        {
                            arr[i] += 2;
                            break;
                        }
                    }
                }
                else
                {
                    procTotal++;
                    // ２個だけ1増やす
                    for (int i = 0; i < arr.Length; ++i)
                    {
                        arr[i] += 1;
                    }
                }
            }
        }
    }
}