#include <bits/stdc++.h>
using namespace std;
int main(){
    int n,a,b,c;
    cin>>n;
    a=n%10;
    b=n/10%10;
    c=n/100;
    if(a<b){
        swap(a,b);
    }
    if(a<c){
        swap(a,c);
    }
    if(b>c){
        swap(b,c);
    }cout<<a-b;
}
/**************************************************************
	Problem: 1667
	User: sucongyi
	Language: C++
	Result: Accepted
	Time:18 ms
	Memory:2072 kb
****************************************************************/