The sieve of Eratosthenes is a famous algorithm to find all prime numbers up to ~N~. The algorithm is:

1. Write down all integers between ~2~ and ~N~, inclusive.
2. Find the smallest number not already crossed out and call it ~P~; ~P~ is prime.
3. Cross out ~P~ and all its multiples that aren't already crossed out.
4. If not all numbers have been crossed out, go to step ~2~.

Write a program that, given ~N~ and ~K~, find the ~K^\text{th}~ integer to be crossed out.

Input Specification

The integers ~N~ and ~K~ ~(2 \le K < N \le 1000)~.

Output Specification

Output the ~K^\text{th}~ number to be crossed out.

Sample Input 1

7 3

Sample Output 1

6

Sample Input 2

15 12

Sample Output 2

7

Sample Input 3

10 7

Sample Output 3

9

In the third example, we cross out, in order, the numbers ~2, 4, 6, 8, 10, 3, 9, 5~ and ~7~. The seventh number is ~9~.