#include<bits/stdc++.h>
using namespace std;
int main(){
int n,g,s,b,c;
cin>>n;
g=n%10;
s=n/10%10;
b=n/100;
int max=g;
if (max<s){
max=s;
}
if (max<b){
max=b;
}
int min=g;
if (min>s){
min=s;
}
if (min>b){
min=b;
}
c=max-min;
cout<<c<<endl;
}
/**************************************************************
Problem: 1667
User: xiaojingxuan
Language: C++
Result: Accepted
Time:8 ms
Memory:2072 kb
****************************************************************/