Challenge 2: Missing Number
In this article, we'll learn various ways to find the missing number in an array. We use a memoization approach, a mathematical approach, and the most optimized way using the XOR operator.

In this article, we'll learn various ways to find the missing number in an array. We use a memoization approach, a mathematical approach, and the most optimized way using the XOR operator.
In this two-sum problem, we use various approaches to solve the problem from brute force to an optimized approach. We also discuss the take-offs and talk about complexity analysis.
In the kth bit set/unset problem, we first write the algorithm, then some pseudocode, and then implement the solution.
This problem is similar to the last lesson we discussed. If you need a clue, return to the previous lesson to further your understanding.