#include<iostream>
#include<string>
using namespace std;

int main()
{
string n;
cin>>n;
int i,l;

for(int i=0;i<n.length();i++)
{
    if(n[i]=='0'||n[i]=='1'||n[i]=='2'||n[i]=='3'||n[i]=='4'||n[i]=='5'||n[i]=='6'||n[i]=='7'||n[i]=='8'||n[i]=='9')
    {
        cout<<n[i];
    }

}
l=n.length();
    if(n[i]!='0'&&n[i]=='1'&&n[i]=='2'&&n[i]=='3'&&n[i]=='4'&&n[i]=='5'&&n[i]=='6'&&n[i]=='7'&&n[i]=='8'&&n[i]=='9'))
    {
        cout<<"-1";
    }


return 0;
}