Check if two arrays are equal as multisets: problem statement, brute force vs sorting vs hash map, a complexity table, edge cases and tested Python and C++ solutions.

Learn how the binary search algorithm finds a value in a sorted array in O(log N), with step-by-step dry runs, a complexity table, Python and C++ code and common pitfalls.

Problem statement, worked examples, three approaches with complexity analysis, and working Python and C++ code for finding the second largest distinct element in an array.

Problem statement, worked examples, three approaches with complexity analysis, and complete Python and C++ code for the classic Missing Number in Array interview question.