#include <bits/stdc++.h>
using namespace std;
int main(){
	int n;
	cin>>n;
	int b = n / 100;
	int s = n / 10 % 10;
	int g = n % 10;
	
	int ma = b;
	int mi = b;
	if(s > ma) ma = s;
	if(s < mi) mi = s;
	if(g > ma) ma = g;
	if(g < mi) mi = g;
	
	cout<<ma - mi;
}

/**************************************************************
	Problem: 1667
	User: admin
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/