cf723a The New Year: Meeting Friends

There are three friend living on the straight line Ox in Lineland. The first friend lives at the point x1, the second friend lives at the pointx2, and the third friend lives at the point x3. They plan to celebrate the New Year together, so they need to meet at one point. What is the minimum total distance they have to travel in order to meet at some point and celebrate the New Year?

It's guaranteed that the optimal answer is always integer.

Input

The first line of the input contains three distinct integers x1, x2 and x3 (1 ≤ x1, x2, x3 ≤ 100) — the coordinates of the houses of the first, the second and the third friends respectively.

Output

Print one integer — the minimum total distance the friends need to travel in order to meet together.

Examples

input

7 1 4

output

6

input

30 20 10

output

20

Note

In the first sample, friends should meet at the point 4. Thus, the first friend has to travel the distance of 3 (from the point 7 to the point 4), the second friend also has to travel the distance of 3 (from the point 1 to the point 4), while the third friend should not go anywhere because he lives at the point 4.

/*
大意：三个sb，住在一条数轴上，要到一个点集合，问最小总距离
这个其实就是中位数啦，无论向左还是向右都不会更优
*/
#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
#include<cmath>
#include<algorithm>
using namespace std;
int n[10],ans;
int main(){
    cin>>n[1]>>n[2]>>n[3];
    sort(n+1,n+4);
    ans = abs(n[2]-n[1]) + abs(n[3]-n[2]);
    cout<<ans;
    return 0;
}