#include <iostream>
#include <algorithm>
#include <map>
#include <vector>
#include <cmath>
using namespace std;

int main()
{
	long long a, b, t; cin >> a >> b >> t;
	int b2 = b, a2 = a;
	if (a > b)swap(a, b);
	vector<pair<int, int> > soinsu[2];
	int i = 2;
	while (a >= i*i){
		if (a%i == 0){
			int cnt = 0;
			while (a%i == 0){
				a /= i;
				cnt++;
			}
			soinsu[0].push_back(make_pair(i, cnt));
		}
		else{
			i++;
		}
	}
	soinsu[0].push_back(make_pair(a, 1));
	i = 2;
	while (b >= i*i){
		if (b%i == 0){
			int cnt = 0;
			while (b%i == 0){
				b /= i;
				cnt++;
			}
			soinsu[1].push_back(make_pair(i, cnt));
		}
		else{
			i++;
		}
	}
	soinsu[1].push_back(make_pair(b, 1));
	long long gcd = 1;
	vector<pair<int,int> >g;
	for (i = 0; i < soinsu[0].size();i++){
			g.push_back(make_pair(soinsu[0][i].first,soinsu[0][i].second));
	}
	for (int j = 0; j < soinsu[1].size(); j++){
		for (i = 0; i < g.size(); i++){
			if (soinsu[1][j].first == g[i].first){
				g[i] = make_pair(g[i].first, max(g[i].second, soinsu[1][j].second));
				break;
			}
			if (i == g.size() - 1)g.push_back(make_pair(soinsu[1][j].first, soinsu[1][j].second));
		}
	}
	for (i = 0; i < g.size(); i++){
		gcd *= pow(g[i].first, g[i].second);
	}
	//cout << gcd << endl;
	int t2 = t;
	t %= gcd;
	if (t + gcd <= t2)t += gcd;
	//cout << t << endl;
	long long mn = 1000000001;
	int x;
	for (i = 0; i*b2 <= t; i++){
		mn = min(mn, (a2 - (t - i*b2)%a2)%a2);
	}
	mn = min(mn, i*b2-t);

	cout << mn + t2 << endl;

	return 0;
}