Kattis

# Reseto

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 $K$-th integer to be crossed out.

## Input

The integers $N$ and $K$ $(1 \leq K < N \leq 100\, 000)$.

## Output

Output the $K$-th number to be crossed out.

Sample Input 1 Sample Output 1
7 3

6

Sample Input 2 Sample Output 2
15 12

7

Sample Input 3 Sample Output 3
10 7

9