#include <bits/stdc++.h>
using namespace std;

int main()
{
  int abc;
  cin >> abc;

  int a = abc / 100 % 10;
  int b = abc / 10 % 10;
  int c = abc / 1 % 10;

  int ans = max({a, b, c}) - min({a, b, c});
  cout << ans << endl;
}