problema 65

#include <iostream>
using namespace std;
int main()
{
    int n,s=1,c=0;
    cin>>n;
    while (n!=0){
        if (n%10%2==1){
        s=s*(n%10);
        c++;}
        n=n/10;
    }
if (c!=0)
    cout<<s;
else
    cout<<-1;
}