Popular Algorithms Coding Interview Questions

Learn to maximize profit with multiple stock transactions by capturing every upward price move and selling, accumulating gains in linear time with constant space.

Detect duplicates in an integer array, sorted or unsorted. Use a hash set to check each element for O(n) time and O(n) space, returning true on duplicates and false otherwise.

Learn to search a rotated sorted array with a modified binary search using left, right, and middle pointers to identify sorted portion and return index or -1 in log time.

Learn to solve the maximum contiguous subarray sum with the cadence algorithm by tracking current and maximum sums as you scan the array, a dynamic programming approach with constant space.

This lecture demonstrates solving the longest increasing subsequence problem with dynamic programming, building a dp table to compute the length in a quadratic time, linear space approach.

Solve the gas station circle problem on a clockwise route by comparing total gas and total cost, then identify a starting station using a running difference and current sum.

Learn to solve the product of array except self without division by building prefix and suffix products, then optimize to constant extra space while maintaining linear time.

Learn to reverse a linked list iteratively using three pointers, updating links to produce the head of the reversed list and noting time and space complexity.

Reverse a linked list recursively, traversing to the last node, using the call stack to reconnect links, and returning the new head. Explore the recursion's time and space implications.