#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,g,s,b,big,small;
    cin>>n;
    g=n%10;
    s=n/10%10;
    b=n/100;
    big=max({g,s,b});
    small=min({g,s,b});
    cout<<big-small;
    return 0;
}