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;
using System.Collections.Generic;
using System.Text;

class Program
{
    static void Main(string[] args)
    {
        // 入力
        int[] abc = Console.ReadLine().Split().Select(int.Parse).ToArray();
        var a = abc[0];
        var b = abc[1];
        var c = abc[2];


        Array.Sort(abc);
        var tmp1 = abc[0];
        var tmp2 = abc[1];
        var max = abc[2];
        var ans = 0;

        bool flag = true;
        while (flag)
        {
            if (max - tmp1 == 0 && max - tmp2 == 0)
            {
                flag = false;
            }
            else if (max - tmp1 > 2)
            {
                tmp1 += 2;
                ans += 1;
            }
            else if (max - tmp2 > 2)
            {
                tmp2 += 2;
                ans += 1;
            }
            else if (max - tmp1 == 2 && max - tmp2 == 2)
            {
                tmp1 += 2;
                tmp2 += 2;
                ans += 2;
                flag = false;
            }
            else if (max - tmp1 == 1 && max - tmp2 == 1)
            {
                tmp1 += 1;
                tmp2 += 1;
                ans += 1;
                flag = false;
            }
            else if (max - tmp1 == 0 && max - tmp2 == 1)
            {
                ans += 2;
                flag = false;
            }
            else if (max - tmp1 == 1 && max - tmp2 == 0)
            {
                ans += 2;
                flag = false;
            }
            else if (max - tmp1 == 0 && max - tmp2 == 2)
            {
                ans += 1;
                flag = false;
            }
            else if (max - tmp1 == 2 && max - tmp2 == 0)
            {
                ans += 1;
                flag = false;
            }
            else
            {
                ans += 3;
                flag = false;
            }
        }

        Console.WriteLine(ans);
    }
}