#include<iostream>
#include<string>
#include<cctype>

using namespace std;
int main(){
    string input, result ="";
    if(result<100()){
        cout<<-1<<endl;
        return 0;
    }
    if(!(cin >> input))return 0;
    for(char c : input){
        if(isdigit(c)){
            result += c;
        }
    }
    if(result.empty()){
        cout<<-1<<endl;
        return 0;
    }else{
        cout<<result<<endl;
    }
    return 0;
}