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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<iostream>
#include<cstdio>
using namespace std;
int a,b,c,mx,cnt;
int main()
{
	cin>>a>>b>>c;
	mx=max(a,max(b,c));
	for (int i=mx;i<=100;i++)
	{
		cnt=0;
		if ((i-a)&1) cnt++;
		if ((i-b)&1) cnt++;
		if ((i-c)&1) cnt++;
		if (cnt%2==0) 
		{
			cout<<(i*3-a-b-c)/2<<endl;
			return 0;
		}
	}
	return 0;
}