Tagged with arrays
Arrays are ordered list-like objects with mutation helpers like `push`, `pop`, `shift`, and `unshift`.
JavaScript arrays, array methods, and push/pop/shift/unshift operations
Modern array work relies on iteration helpers, search helpers, and knowing which methods mutate the original array.
slice vs splice, map, filter, reduce, forEach, find, some, every, includes, sort, reverse, and array destructuring
Spread expands values, rest collects remaining values, and destructuring pulls parts of arrays or objects into variables.
Spread operator, rest operator, and destructuring assignment in JavaScript
Sort the array, fix one value at a time, and use two pointers on the remaining range. Skip duplicate anchors and duplicate pointer values so the result contains unique triplets only.
Return all unique triplets in an array whose sum is zero.
Walk the array once, keep the lowest price so far, and compute the best profit if you sold today.
Find the maximum profit from one buy and one sell of a stock price series.
Use left and right pointers, compute the middle index, and discard half the range each step based on the comparison.
Given a sorted list and a target, return the target index or -1 if it is missing.
Use left and right pointers, compute the current area, and always move the side with the smaller height because only that can improve the limiting wall.
Find two lines that together hold the maximum area of water.
Walk the list once, keep a set of seen values, and add repeated values into a duplicate set. Convert to a sorted list if stable output helps.
Return the duplicate values from a list of integers.
Track the best result when including or excluding the current house. A rolling two-variable DP solution keeps the implementation compact.
Return the maximum amount you can rob from houses without robbing adjacent houses.
Convert both arrays to sets, intersect them, and sort the result if you want deterministic output for testing or interviews.
Return the unique values that appear in both arrays.