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

namespace AtCoder_ABC089_A
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] s = Console.ReadLine().Split(' ');

            int a = int.Parse(s[0]);
            int b = int.Parse(s[1]);
            int c = int.Parse(s[2]);

            int _1st, _2nd, _3rd;

            if (a > b)
            {
                if (a > c)
                {
                    _1st = a;

                    if (b > c)
                    {
                        _2nd = b;
                        _3rd = c;
                    }
                    else
                    {
                        _2nd = c;
                        _3rd = b;
                    }
                }
                else
                {
                    _1st = c;
                    _2nd = a;
                    _3rd = b;
                }
            }
            else
            {
                if (b > c)
                {
                    _1st = b;

                    if (a > c)
                    {
                        _2nd = a;
                        _3rd = c;
                    }
                    else
                    {
                        _2nd = c;
                        _3rd = a;
                    }
                }
                else
                {
                    _1st = c;
                    _2nd = b;
                    _3rd = a;
                }
            }


            int count = _1st - _2nd;

            int sub = _2nd - _3rd;

            count += sub / 2;

            if (sub % 2 == 1)
            {
                count += 2;
            }

            Console.WriteLine(count);
        }
    }
}