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

int main()
{
string n,k;
getline(cin,n);
int i,l;
if(n.length()<100&&n.length()>0)
for(int i=0;i<n.length();i++)
{
    if()
    {
        
    }
    else if(n[i-1]=='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];
        k=n[i];
    }
    

}
if(k.length()==0)
{
    cout<<"-1";
}

return 0;
}