#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;
using str = string;
const int N = 2e5 + 3, INF = 1e9;

int main()
{
    ios :: sync_with_stdio(0);
    cin.tie(), cout.tie();
    ll w, h, n;
    cin >> w >> h >> n;
    ll l = 0, r = max(w * n, h * n);
    while(l < r){
        ll m = (l + r) / 2;
        if((m / h) * (m / w) >= n) r = m;
        else l = m + 1;
    }
    cout << l;

    return 0;
}