#include <iostream>
using namespace std;
int main(){
    int a,b,c;cin>>a>>b>>c;
    int ans = abs(a-c);
    if(b > a && b > c){
        ans = min(ans,b-max(a,c));
    }
    if(0 < max(a,c)-b)ans = min(ans,max(a,c)-b);
    cout << ans << endl;
}