import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long a = sc.nextInt();
        long b = sc.nextInt();
        long t = sc.nextInt();
        long lcm = a / gcd(a, b) * b;
        long total = t % lcm;
        long min = Long.MAX_VALUE;
        for (int i = 0; i * a < total; i++) {
            min = Math.min(min, (total - i * a + b - 1) / b * b - total + i * a);
        }
        min = Math.min(min, (total + a - 1) / a * a - total);
        System.out.println(t + min);
    }
    
    static long gcd(long x, long y) {
        if (x % y == 0) {
            return y;
        } else {
            return gcd(y, x % y);
        }
    }
}