Build a Binary Search Tree from a preorder sequence
Given a distinct sequence of keys representing the preorder sequence of a binary search tree (BST), construct a BST from it.
Tag: Recursive
Check if a linked list of strings is palindromic
Given a linked list of strings, check whether the concatenation of all values in the list together forms a palindrome. It is not permissible to construct a string out of the linked list nodes and check that string for palindrome.
Recursive solution to sort a stack
Given a stack, sort it using recursion. The use of any other data structures (like containers in STL or Collections in Java) is not allowed.
Ways to reach the bottom-right corner of a matrix with exactly `k` turns allowed
Given an M × N matrix, count the number of different ways to reach the bottom-right corner of a matrix from its top-left corner with exactly k turn allowed and using only the directions right and down.
Flatten a multilevel linked list
Given a list that can grow in both horizontal and vertical directions (right and down), flatten it into a singly linked list. The conversion should be in such a way that the down node should be processed before the next node for any node.
Set next pointer to the inorder successor of all nodes in a binary tree
Given a binary tree where each node has one extra pointer next, set it to the inorder successor for all binary tree nodes.
Efficiently print all nodes between two given levels in a binary tree
Given a binary tree, efficiently print all nodes between two given levels in a binary tree. The nodes for any level should be printed from left to right.
Sort an array using Young tableau
In this post, we will see how to sort N^2 numbers in increasing order using an N × N Young tableau in O(N^3) time.
Young Tableau | Insert, Search, Extract-Min, Delete, Replace
An M × N Young tableau is an M × N matrix such that the entries of each row are sorted from left to right and the entries of each column are sorted from top to bottom. Some entries of a Young tableau may be infinity, which indicates an empty entry.
Find the path between given vertices in a directed graph
Given a directed graph and two vertices (say source and destination vertex), determine if the destination vertex is reachable from the source vertex or not. If a path exists from the source vertex to the destination vertex, print it.
Weighted Interval Scheduling Problem
Given a list of jobs where each job has a start and finish time, and has profit associated with it, find a maximum profit subset of non-overlapping jobs.
Find difference between sum of all nodes present at odd and even levels in a binary tree
Given a binary tree, calculate the difference between the sum of all nodes present at odd levels and the sum of all nodes present at even level.