#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
using namespace std;

int main() {
    char c[3];
    int mx = 0;
    int mn = 10;
    rep(i, 3) {
        cin >> c[i];
        int a = c[i] - '0';
        mx = max(a, mx);
        mn = min(a, mn);
    }
    cout << mx - mn << endl;
    return 0;
}