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.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using static System.Console;
using static System.Math;
class Simple {
    void Solve() {
        var A = io.Int;
        var B = io.Int;
        var C = io.Int;
        var ABC = new int[] {A, B, C};
        var ans = 0;
        while(ABC.Max() - ABC.Min() >= 2) {
            if(ABC[0] == ABC.Min()) {
                ABC[0] += 2;
            } else if(ABC[1] == ABC.Min()) {
                ABC[1] += 2;
            } else {
                ABC[2] += 2;
            }
            ans++;
        }
        var sameMax = ABC.Where(x => x == ABC.Max()).Count();
        if(sameMax == 3) {
            //
        } else if(sameMax == 2) {
            ans += 2;
        } else { //sameMax = 1
            ans++;
        }        
        WriteLine(ans);
    }
    SimpleIO io = new SimpleIO();
    public static void Main(string[] args) => new Simple().Stream();
    private void Stream() {
        //var exStdIn = new System.IO.StreamReader("stdin.txt");
        //SetIn(exStdIn);
        Solve();
        io.Flush();
    }
}
class SimpleIO {
    string[] _nextBuffer;
    int _bufferCnt;
    char[] cs = new char[] {' ', '"', ','};
    StreamWriter sw = new StreamWriter(OpenStandardOutput()) {
#if DEBUG
        AutoFlush = true
#else
        AutoFlush = false
#endif
    };
    public SimpleIO() {
        _nextBuffer = new string[0];
        _bufferCnt = 0;
        SetOut(sw);
    }
    string Next() {
        if(_bufferCnt < _nextBuffer.Length)
            return _nextBuffer[_bufferCnt++];
        var st = ReadLine();
        while(st == "")
            st = ReadLine();
        _nextBuffer = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
        _bufferCnt = 0;
        return _nextBuffer[_bufferCnt++];
    }
    public string String => Next();
    public char Char => char.Parse(String);
    public int Int => int.Parse(String);
    public long Long => long.Parse(String);
    public double Double => double.Parse(String);
    public void Flush() => Out.Flush();
}