#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
long long a, b, k;
long long lcm, sum, ans;
bool solve(long long x) {
    long long s = x / a + x / b;
    if (s < k % sum) {
        return true;
    }
    else {
        return false;
    }
}
long long gcd(long long a, long long b) {
    if (a % b == 0) {
        return (b);
    }
    else {
        return (gcd(b, a % b));
    }
}
int main() {
    cin >> a >> b >> k;
    if (a == b) {
        cout << a * k << endl;
        return 0;
    }
    lcm = a * b / gcd(a, b);
    sum = lcm / a + lcm / b - 1;
    ans = k / sum * lcm;
    long long l = 1, r = 1000000000000000007;
    while (r - l > 1) {
        long long mid = (l + r) / 2;
        if (solve(mid)) {
            l = mid;
        }
        else {
            r = mid;
        }
    }
    cout << k / sum * lcm + r << endl;
}