//  Brankonymous //

#include <bits/stdc++.h>

#define ios ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define rep(i,l,r) for (int i=l;i<=r;i++)
#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define ll long long
#define mod 1000000007
#define random_jbt mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

using namespace std;

int main(){
    ios;
    
    string s,a,b,ans;
    cin>>s;
    a=b=s;
    sort(all(b));
    sort(rall(a));

    for (int i=s.size()-1;i>=0;i--){
        if (a[i]>=b[i])ans+=(a[i]-b[i])+'0';
        else{
            int x=a[i]-'0';
            int y=b[i]-'0';
            while(x<y){
                x+=10;
                a[i-1]--;
            }
            ans+=(x-y)+'0';
        }
    }
    while(ans.size()>1 and ans.back()=='0')ans.pop_back();
    reverse(all(ans));
    cout<<ans;
    return 0;
}