#include<iostream>
using namespace std;
int main() {
	int k, a, b, c,m,n;
	cin >> k;
	c = k % 10;
	k /= 10;
	b = k % 10;
	k /= 10;
	a = k;
	m = max(max(a, b),c);
	n = min(min(a, b),c);
	cout << m - n << endl;
	return 0;
}