#include <iostream>
#include <cstdio>
#include <vector>
#include <string>
#include <sstream>
#include <map>
#include <queue>
#include <stack>
#include <algorithm>
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)

using namespace std;

int ans = 0x7fffffff;
int sum = 0;
int A, B, T;
void setSum(int _sum) {
	sum = _sum;

	if ( sum < ans && T <= sum ) ans = sum;
}

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

	if ( T % A == 0 || T % B == 0 ) {
		cout << T << endl;
		return T;
	}

	int count = (T / A) + 1;
	
	setSum( A * count );

	while ( count-- ) {
		int next = sum - A;
		while (next < T) next += B;
		setSum( next );

		if ( sum == T ) break;
	}

	cout << ans << endl;

	return 0;
}