Capacity vs. Length
Array capacity is how many items an array can hold, and array length is how many items an array currently has. "Learn all about arranging array elements in this comprehensive article."
Solution Review: Single Number
Single Number coding question, can be easily solved with XOR bitwise technique with linear time complexity.
Challenge 2: Single Number
In this lesson, every element appears twice except one element. We solve this using naive, and then we move to solve it more optimally using XOR operator.
Solution Review: Missing Number
We solved the problem using lookup (hashtable), using the mathematical formula. Let's solve this more efficiently using bit-level operations with XOR and then optimize the solution.