#include <iostream>
#include <string>
using namespace std;
int main(void){
    string s;
    cin >> s;
    int m = 10, M = -1, a;
    for (int i = 0; i < 3; i++) {
        a = stoi(s.substr(i, 1));
        m = min(m, a);
        M = max(M, a);
    }
    cout << M - m << endl;
}