#include <iostream>

using namespace std;
long long a,b,c,n,p,db,i,k,r;
int main()
{
    for(k=1;k<=3;++k)
    {
        cin>>a>>b>>n;
        p=a*b;
        r=a%b;
        while(r>0)
        {
            a=b;
            b=r;
            r=a%b;
        }

       // cout<<b<<"  ";
        b=p/b;
        c=b;

        db=0;

        while(c>0)
        {
            ++db;
            c=c/10;
        }

        if(db<=n)
        {
            cout<<b;
            for(i=db;i<n;++i)
                cout<<0;

        }
        else cout<<-1;

        cout<<"\n";
    }
}