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 (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>

int main()
{
	int A,B,C,max,mid,min,count,min2,mid2;
	
	scanf("%d %d %d", &A,&B,&C);
	count = 0;
	if(A>B)
	{
		if(C>A)
		{
			max = C; min = B; mid = A;
		}
		else
		{
			max = A;
			if(C>B){
				mid = C; min = B;
			}
			else {
				mid = B; min = C;
			}
		}
	}
	else
	{
		if(C>B)
		{
			max = C; min = A; mid = B; 
		}
		else
		{
			max = B;
			if(C>A) {
				mid = C; min = A;
			}
			else {
				mid = A; min = C;
			}
		}
	}
	
	count += (max-min)/2;
	count += (max-mid)/2;
	min2 = max - (max-min)%2;
	mid2 = max - (max-mid)%2;
	
	if(mid2 == min2 && mid2 == max)
	{
		count += 0;
	}
	else if(mid2 == min2)
	{
		count += 1;
	}
	else
	{
		count += 2;
	}
	
	printf("%d\n",count);
	
	return 0;
}