Small Count
CONCEPTS USED: Binary Search DIFFICULTY LEVEL: Hard PROBLEM STATEMENT(SIMPLIFIED): Given an array A containing N elements, construct a new array countSmaller[] such that countSmaller[i] contains count of smaller elements on...
Remove Kth element from Min Heap
Concepts Used : Heap Difficulty Level : Easy Problem Statement : Given an array containing N integers, our task is to: Create min-heap with 1 based indexing. Remove the element...
Print first K non-repeating characters of a string
Concepts Used: Heap Difficulty Level: Hard Problem Statement : Given a string str, find first K non-repeating characters in lexicographical order, if all the characters are repeating then print "Not...
Heap Sort
Concepts Used: Heap Difficulty Level: Easy Problem Statement : Given an array containing N integers, our task is to create a min-heap using the elements of the given array and...
Minimum Difference
Concepts Used Heap Difficulty Level: Hard Problem Statement : Given N sectors and two integers P and Q, our task is to find Q closest sectors to P sector. Solution...
Kth Largest element
In the realm of data structures, heaps stand out as an essential tool for efficient manipulation of priority-based information. One common problem encountered when dealing with heaps is finding the...
Kth Smallest Number
Concepts Used Heap Difficulty Level Easy Problem Statement : Given an array arr[ ] and a number K where K is smaller than the size of the array, the task...
Small String
Concepts Used Heap Difficulty Level Medium Problem Statement : Given a string str and an integer q. We have to generate a string S such that it is lexicographically smallest...
Maximum Books
Concepts Used Heap Difficulty Level Medium Problem Statement : We are given N book costs, and k amount of money. We need to find the maximum number of books we...
Prizes
Concepts Used Heap Difficulty Level Easy Problem Statement : Given N integers where a[i] represent that a[i]th student has won the ith competition. Print top Q students who have won...
Ball Firing Game
Concepts Used Sorting Difficulty Level Hard Problem Statement (Simplified): For given two arrays, print the score of First Array and Second Array such that their difference is maximum. Scoring can...
Aman Arithmetic progression
Concepts Used Sorting Difficulty Level Medium Problem Statement (Simplified): Print the total number of cases in which the current array sequence becomes Arithmetic Progression by adding a number at any...
Copying Hero
Concepts Used Sorting Difficulty Level Medium Problem Statement (Simplified): We need to find the total number of steps need to make the current array of size N same as an...
Plagiarism Test
Concepts Used BFS , Recursion Difficulty Level Easy Problem Statement : Given a binary tree, and a node X, we have to sum all the nodes except the node X....
Sum Query
Concepts Used Segment Trees Difficulty Level Easy Problem Statement : Given an array of N elements and Q queries. In each query he is given two values l,r. We have...
Maximum Divisor
Concepts Used Segment Trees, GCD Difficulty Level Medium Problem Statement : Given an array of N elements and Q queries. In each query, two values is given l and r....
Consecutive Permutation
Concepts Used Segment Trees Difficulty Level Hard Problem Statement : Given an array of N unique elements and Q queries. In each query, we are given two values l,r. We...
XOR Maximum
Concepts Used Trie Difficulty Level Medium Problem Statement : Given array of N numbers, we need to find the maximum xor between any pair of the numbers. Solution Approach :...
Find words
Concepts Used Trie Difficulty Level Easy Problem Statement : Given a blank dictionary. Now in the first set of operations, you have to insert N integers in the dictionary. And...
Tug of War
Concepts Used Back Tracking Difficulty Level Hard Problem Statement : Given a set of n integers, divide the set in two subsets of n/2 sizes each such that the difference...
Unique Power Set
Concepts Used Back Tracking Difficulty Level Medium Problem Statement : Given N integers print all the distinct power sets of the sequence in lexicographical order. Solution Approach : Introduction :...
Possible Numbers
Concepts Used Back Tracking Difficulty Level Easy Problem Statement : Given a string, we have to find total number of different sequences that can be formed using the letters in...
Phone Number
Concepts Used Backtracking Difficulty Level Easy Problem Statement : Given a string containing numeric digits from 2 to 9 inclusive, return all possible letter combinations that the number could represent...
Possible Attack-2
Concepts Used Back Tracking Difficulty Level Hard Problem Statement : Given N integers print all distinct combinations. Solution Approach : Introduction : Idea is to swap all the values one-by-one...
Grey Code
Concepts Used Back Tracking Difficulty Level Hard Problem Statement : Given a non-negative integer n representing the total number of bits , we need to print the sequence of gray...
Time Bits
Concepts Used Back Tracking Difficulty Level Easy Problem Statement : Given n set bits, we have to determine all the time that can be represented by those number of set...
Creating Words
Concepts Used Back Tracking Difficulty Level Hard Problem Statement : Given a matrix of characters with n rows and m columns, and few words. We have to find out if...
Possible Attack-1
Concepts Used Back Tracking Difficulty Level Medium Problem Statement : Given N integers print all possible combinations. Solution Approach : Introduction : Idea is to swap all the values one-by-one...
M Coloring Problem
Given an undirected graph and M colors, the problem is to find if it is possible to color the graph with at most M colors or not. How to Solve...
Furious Teacher
Concepts Used Back Tracking Difficulty Level Medium Problem Statement : Given N, count all the numbers with unique digits less than 10n. Solution Approach : Introduction : Idea is to...