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;

namespace AtCoder.ABC093
{
    class c
    {
        static void Main(string[] args)
        {
            var line = Console.ReadLine().Trim();
            var spl = line.Split(' ');
            var A = int.Parse(spl[0]);
            var B = int.Parse(spl[1]);
            var C = int.Parse(spl[2]);
            var max = Math.Max(A, Math.Max(B, C));
            var div = 3 * max - (A + B + C);
            if (div % 2 == 0)
            {
                Console.WriteLine(div / 2);
            }
            else
            {
                Console.WriteLine((div + 3) / 2);
            }
        }
    }
}