#include <bits/stdc++.h> 
using namespace std;
using ll =long long;
#define all(v) v.begin(),v.end()
 #define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)

int main() {
    string S;cin>>S;
    ll ma=0;
    ll mi=9;
    for(ll i=0;i<3;i++) {
        ma=max(ma,(ll)(S[i]-'0'));
        mi=min(mi,(ll)(S[i]-'0'));
    }
    cout<<ma-mi<<endl;
}