// a sarkany feladvany.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <string>

using namespace std;

long long a, b, c, i, j, l, lkkt, szam, r, p;
string s;

int main()
{
    for (i = 1; i <= 3; ++i)
    {
        cin >> a >> b >> l;

        p = a * b;
        r = a % b;
        while (r>0)
        {
            a = b;
            b = r;
            r = a % b;
        }
        szam = lkkt = p / b;

        s = to_string(szam);

        if (s.size() <= l)
        {
            cout << lkkt;
            for (j = 1; j <= l - s.size(); ++j) cout << 0;
        }
        else cout << -1;
        cout << "\n";
    }
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file