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<cstdio>
#include<cmath>
#include<algorithm>
#include<cstdlib>
#include<cstring>
using namespace std;
int a[3],ans; 
int main(){
	scanf("%d%d%d",&a[0],&a[1],&a[2]);
	sort(a,a+3);
	while(a[1]<a[2]){
		a[0]++;
		a[1]++;
		ans++;
	}
	while(a[0]<a[1]){
		a[0]+=2;
		ans++;
	}
	if(a[1]!=a[0])
		ans++;
	printf("%d\n",ans);
	return 0;
}