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.Text;
using System.Collections.Generic;
using System.Linq;
using E = System.Linq.Enumerable;
 
class Program
 {
        static void Main(string[] args)
        {
          //入力を受け取る
          var ABC = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToArray();
          int A = ABC[0];
          int B = ABC[1];
          int C = ABC[2];
          
          if(A<B){
            var tmp = A;
            A = B;
            B = tmp;
          }
          if(A<C){
            var tmp = A;
            A = C;
            C = tmp;
          }
          var sa = (A-C)+(A-B);
          
          if(sa%2 == 0){
            Console.WriteLine(sa/2);
          }else{
            Console.WriteLine(sa/2+2);
          }
        }
  
}