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

namespace competitive_programming
{
    class Program
    {
        static void Main(string[] args)
        {
            var main = new Program();
            main.solve();
        }

        void solve()
        {
            int[] abc = Console.ReadLine().Split(' ').Select(val => int.Parse(val)).ToArray();
            int a = abc[0];
            int b = abc[1];
            int c = abc[2];

            int count = 0;

            while (true)
            {
                if (a == b && b == c)
                {
                    Console.WriteLine(count);
                    return;
                }
                else if (a == b)
                {
                    if (a < c)
                    {
                        a++;
                        b++;
                        count++;
                    }
                    else
                    {
                        c += 2;
                        count++;
                    }
                }
                else if (b == c)
                {
                    if (a < b)
                    {
                        a += 2;
                        count++;
                    }
                    else
                    {
                        b++;
                        c++;
                        count++;
                    }
                }
                else if (a == c)
                {
                    if (a > b)
                    {
                        b += 2;
                        count++;
                    }
                    else
                    {
                        a++;
                        c++;
                        count++;
                    }
                }
                else
                {
                    if (a < b && b < c)
                    {
                        a += 2;
                        count++;
                    }
                    else if (a < c && c < b)
                    {
                        a += 2;
                        count++;
                    }
                    else if (b < a && a < c)
                    {
                        b += 2;
                        count++;
                    }
                    else if (b < c && c < a)
                    {
                        b += 2;
                        count++;
                    }
                    else if (c < a && a < b)
                    {
                        c += 2;
                        count++;
                    }
                    else
                    {
                        c += 2;
                        count++;
                    }
                }
            }
        }
    }
    struct Vector2
    {
        public Vector2(long x, long y)
        {
            this.x = x;
            this.y = y;
        }
        public long x;
        public long y;
    }

    struct Vector3
    {
        public int x;
        public int y;
        public int z;
    }
}