Kth Prime Factor
Easy Accuracy: 13.33% Submissions: 324 Points: 2

Given two numbers n and k, find the kth prime factor of n. 

Example 1:

Input: n = 225, k = 2
Output: 3
Explaination: The prime factors 3, 3, 5 
and 5. So 3 is the 2nd one.

Example 2:

Input: n = 81, k = 5
Output: -1
Explaination: The 4 prime factors are 
3, 3, 3, 3. So there is no 5th one.

Your Task:
You do not need to read input or print anything. Your task is to complete the function kthPrime() which takes the value n and k as input parameters and return the kth prime number. If k is greater than total number of primes then return -1.

Expected Time Complexity: O(n*log(log n))
Expected Auxiliary Space: O(n)

1 ≤ n ≤ 104
1 ≤ k ≤ 50

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Kth Prime Factor

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