import java.util.Arrays;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Scanner;
import java.util.Set;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		final long A = sc.nextLong();
		final long B = sc.nextLong();
		final long T = sc.nextLong();
		
		final long max = Math.max(A, B);
		final long min = Math.min(A, B);
		
		Set<Long> hash = new HashSet<Long>();
		long answer = Long.MAX_VALUE;
	
		for(long i = (T + max - 1) / max; i >= 0; i--){
			long value = i * max;
			value += Math.max(0, (T - value + min - 1) / min * min);
			//System.out.println(value);
			
			if(hash.contains(value)){
				break;
			}else{
				answer = Math.min(answer, value);
				hash.add(value);
			}
		}
		
		System.out.println(answer);	
	}

}