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Get StartedGiven a circular integer array, find the next greater element for every element in it. The next greater element of an element x in the array is the first larger number to the next of x.
A triangulation of a convex polygon results in a set of non-intersecting diagonals between non-adjacent vertices, which completely partition the interior of the convex hull of the polygon into triangles.
Suppose you are given n red and n blue water jugs, all of different shapes and sizes. All red jugs hold different amounts of water, as do the blue ones. Moreover, there is a blue jug for every red jug that holds the same amount of water and vice versa.
Write an efficient algorithm to invert alternate levels of a perfect binary tree.
Write an efficient algorithm to construct a binary tree from given inorder and level-order sequence.
Given three sorted arrays of variable length, efficiently compute the minimum range with at least one element from each array.
Write an efficient algorithm to construct a binary tree from the given inorder and postorder traversals.
Write an efficient code to clone a linked list with each node containing an additional random pointer. The random pointer can point to any random node of the linked list or null.
Given a binary search tree (BST), efficiently convert it into a min-heap. In order words, convert a binary search tree into a complete binary tree where each node has a higher value than its parent’s value.
Given a binary tree, convert it into a doubly-linked list following the spiral order.
Given an M × N matrix of integers whose each cell can contain a negative, zero, or a positive value, determine the minimum number of passes required to convert all negative values in the matrix positive.
Write an efficient code to clone a binary tree with each node containing an additional random pointer. The random pointer can point to any random node of the binary tree or can be null.