#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
using namespace std;

int main(){
	long long A,B,T;
	cin >> A >> B >> T;

	long long k = min(T/(A+B), A*B);

	long long ans = 1LL<<60;
	if(T%A==0 || T%B==0) ans = T;
	if(A>T) ans = min(ans, A);
	if(B>T) ans = min(ans, B);

	for(int i=0; i<=k+1; i++){
		long long rem = ( T%(A+B) + i*(A+B) );
		if(rem > T) continue;
		ans = min(ans, (rem/A + (rem%A?1:0) )*A + (T - rem) );
		ans = min(ans, (rem/B + (rem%B?1:0) )*B + (T - rem) );
		ans = min(ans, (rem/(A+B) + (rem%(A+B)?1:0) )*(A+B) + (T - rem) );
	}

	cout << ans << endl;

	return 0;
}