#include <iostream>
#define ll long long
using namespace std;

int main(){
    int n,m,a,b;
    cin >> n;
    m = n / 100;
    a = n / 10 % 10;
    b = n % 10;
    if(m > a && a > b){
        cout << m - b << endl;
    }else if(m > b && b > a){
        cout << m - a << endl;
    }else if(a > m && m > b){
        cout << a - b << endl;
    }else if(a > b && b > m){
        cout << a - m << endl;
    }else if(b > a && a > m){
        cout << b - m << endl;
    }else if(b > m && m > a){
        cout << b - a << endl;
    }
}