#include <iostream>
#include <string>
#include <algorithm>
#include <utility>
#include <cmath>
#include <cstdlib>
#include <map>
#include <set>
#include <queue>
#include <vector>
using namespace std;

int main() {
	int abc; cin >> abc;
	int c = abc % 10; abc /= 10;
	int b = abc % 10; abc /= 10;
	int a = abc % 10;
	cout << max(a, max(b, c)) - min(a, min(b, c)) << endl;
}