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(void){
	int a,b,c,tmp;
	scanf("%d %d %d",&a,&b,&c);
	if(a<c){
		tmp = c;
		c = a;
		a = tmp;
	}
	if(a<b){
		tmp = b;
		b = a;
		a = tmp;
	}
	if(b<c){
		tmp = b;
		b = c;
		c = tmp;
	}
	if((b-c)%2==0) printf("%d\n",a-(b+c)/2);
	else         printf("%d\n",a-(b+c-3)/2);
	return 0;
}