# Category Archives: Advanced Data Structure

Quadtrees are trees used to efficiently store data of points on a two-dimensional space. In this tree, each node has at most four children. We… Read More »

## Number of elements less than or equal to a given number in a given subarray

Given an array ‘a[]’ and number of queries q. Each query can be represented by l, r, x. Your task is to print the number… Read More »

## Auto-complete feature using Trie

We are given a Trie with a set of strings stored in it. Now the user types in a prefix of his search query, we… Read More »

## Dynamic Connectivity | Set 1 (Incremental)

Dynamic connectivity is a data structure that dynamically maintains the information about thee connected components of graph. In simple words suppose there is a graph… Read More »

## Ropes Data Structure (Fast String Concatenation)

One of the most common operations on strings is appending or concatenation. Appending to the end of a string when the string is stored in… Read More »

## Left-Child Right-Sibling Representation of Tree

An n-ary tree in computer science is a collection of nodes normally represented hierarchically in the following fashion. The tree starts at the root node.… Read More »

## Find whether a subarray is in form of a mountain or not

We are given an array of integers and a range, we need to find whether the subarray which falls in this range has values in… Read More »

## Print Kth character in sorted concatenated substrings of a string

Given a string of lower alphabetic characters, find K-th character in a string formed by substrings (of given string) when concatenated in sorted form. Examples:… Read More »

## Substring with highest frequency length product

Given a string which contains lower alphabetic characters, we need to find out such a substring of this string whose product of length and frequency… Read More »

## BK-Tree | Introduction & Implementation

BK Tree or Burkhard Keller Tree is a data structure that is used to perform spell check based on Edit Distance (Levenshtein distance) concept. BK… Read More »

## Palindromic Tree | Introduction & Implementation

We encounter various problems like Maximum length palindrome in a string, number of palindromic substrings and many more interesting problems on palindromic substrings . Mostly… Read More »

## Word formation using concatenation of two dictionary words

Given a dictionary find out if given word can be made by two words in the dictionary. Note: Words in the dictionary must be unique… Read More »

## Palindrome pair in an array of words (or strings)

Given a list of words, find if any of the two words can be joined to form a palindrome. Examples: Input : list[] = {“geekf”,… Read More »

## Print all valid words that are possible using Characters of Array

Given a dictionary and a character array, print all valid words that are possible using characters from the array. Examples: Input : Dict – {“go”,”bat”,”me”,”eat”,”goal”,… Read More »