#include<iostream>
#include<string>
using namespace std;
int main(){
    string s;
    cin>>s;
    bool a = false;
    for(char c:s){
        if(c>='0' && c<='9'){
            cout <<c;
            a = true;
        }
    }
    if(!a)
      cout<,-1;
    return 0;  
}