#include<bits/stdc++.h> using namespace std; int main(){ string s; cin>>s; if(s=="10"){ cout<<0; return 0; } int k=0; for(int i=0;i<s.size();i++)k+=s[i]-'0'; for(int i=s.size()-1;i>=0;i--){ if (s[i]!='0'){ s[i]--; for (int j=i+1;j<s.size();j++)s[j]='9'; int new_k=0; for (int j=0;j<s.size();j++)new_k+=s[j]-'0'; if (new_k==k-1){ cout<<stoi(s)<<endl; break; } } } return 0; }