Hey y’all, I’ve seen one too many candidates get tripped up by this problem, so I decided to go over it: Leetcode 1539 Kth Missing Positive Number and its variant.

It’s roughly 50/50 whether you get asked the OG or the variant, so please prepare for both. The difference is extremely subtle but what if you had to find the Kth missing positive number from the first element?

I realize most of us rote memorize the solution but it doesn’t (and shouldn’t) be that way. Among other reasons, short-term memory is hugely unreliable (even across a week’s duration) to memorize LC31 Next Permutation (and its Previous Permutation Variant), LC1047 Candy Crush-ish Variant and now, this problem.

As surprising as it may sound, there is intuition behind this LC question, so make sure you watch the explanation!

Check it out (or not!):
Leetcode 1539 Kth Missing Positive Number

Reference to all of the Meta Variants: https://leetcode.com/discuss/post/6615244/meta-variant-compilation-by-codingwithmi-0pm7/

Good luck on your phone screens & onsite loops.