1.Find pair with given sum in the array 2.Check if subarray with 0 sum is exists or not 3.Print all sub-arrays with 0 sum

4.Sort binary array in linear time

5.Find a duplicate element in a limited range array 

6.Find largest sub-array formed by consecutive integers 

7.Find maximum length sub-array having given sum 

8.Find maximum length sub-array having equal number of 0’s and 1’s 9.Sort an array containing 0’s, 1’s and 2’s (Dutch national flag problem) 10.Inplace merge two sorted arrays 

11.Merge two arrays by satisfying given constraints 

12.Find index of 0 to replaced to get maximum length sequence of continuous ones

13.Find maximum product of two integers in an array 

14.Shuffle a given array of elements (Fisher–Yates shuffle) 

15.Rearrange the array with alternate high and low elements 

16.Find equilibrium index of an array 

17.Find majority element in an array (Boyer–Moore majority vote algorithm) 18.Move all zeros present in the array to the end 

19.Replace each element of array with product of every other element without using / operator

20.Find Longest Bitonic Subarray in an array

21.Find maximum difference between two elements in the array by satisfying given constraints 

22.Maximum subarray problem (Kadane’s algorithm) 23.Print continuous subarray with maximum sum 24.Maximum Sum Circular Subarray 

25.Find all distinct combinations of given length 

26.Find all distinct combinations of given length with repetition allowed 

27.Find maximum sequence of continuous 1’s formed by replacing at-most k zeroes by ones 

28.Find minimum sum subarray of given size k 

29.Find subarray having given sum in given array of integers 

30.Find the length of smallest subarray whose sum of elements is greater than the given number 

31.Find largest number possible from set of given numbers 

32.Find the smallest window in array sorting which will make the entire array sorted 

33.Find maximum sum path involving elements of given arrays 

34.Maximum profit earned by buying and selling shares any number of times 35.Trapping Rain Water within given set of bars 

36.Longest Increasing Subsequence 

37.Longest Decreasing Subsequence Problem 

38.Find maximum product subarray in a given array 

39.Find maximum sum of subsequence with no adjacent elements 

40.Find minimum platforms needed in the station so to avoid any delay in arrival of any train 

41.Decode the array constructed from another array 42.Sort an array using one swap 

43.Find Triplet with given sum in an array 

44.Length of longest continuous sequence with same sum in given binary arrays 

45.Rearrange array such that A[A[i]] is set to i for every element A[i] 

46.Reverse every consecutive m elements of the given subarray 47.Maximum Product Subset Problem 

48.Find pairs with given difference k in the array 

49.Find pairs with given difference k in the array | Constant space solution 50.4 sum problem | Quadruplets with given sum 51.Print all quadruplets with given sum | 4-sum problem extended 

52.Find odd occurring element in an array in single traversal 

53.Find two odd occurring element in an array without using any extra space 54.Quickselect Algorithm 

55.Print all Triplets that forms Arithmetic Progression 

56.Print all triplets that forms Geometric Progression 

57.Print all combination of numbers from 1 to n having sum n 

58.Replace each element of the array by its corresponding rank in the array 59.Print all Triplets in an array with sum less than or equal to given number 60.Group elements of an array based on their first occurrence 

61.Find minimum difference between index of two given elements present in the array 

62.Find maximum absolute difference between sum of two non-overlapping sub-arrays 

63.Find all Symmetric Pairs in an Array of Pairs 

64.Partition an array into two sub-arrays with the same sum 65.Find count of distinct elements in every sub-array of size k 66.Find two numbers with maximum sum formed by array digits 67.Print all sub-arrays of an array having distinct elements 

68.Find a Triplet having Maximum Product in an Array 

69.Find ways to calculate a target from elements of specified array 70.Find Minimum Index of Repeating Element in an Array 

71.Generate Random Input from an Array according to given Probabilities 72.Find pair in an array having minimum absolute sum 

73.Find Index of Maximum Occurring Element with Equal Probability 74.Check if an Array is Formed by Consecutive Integers 

75.Find two non-overlapping pairs having same sum in an array 

76.Find Minimum Product among all Combinations of Triplets in an Array 

77.Replace every element of an array with the least greater element on its right 

78.Find all odd occurring elements in an array having limited range of elements 

79.Add elements of two arrays into a new array 80.Count the distinct absolute values in the sorted array 

81.Print all combinations of positive integers in increasing order that sum to a given number 

82.Find all distinct combinations of given length  —  Part 2 83.Find subarrays with given sum in an array 

84.Find the surpasser count for each element of an array 

85.Find maximum length sequence of continuous ones (Using Sliding Window) 

86.Find maximum length sequence of continuous ones 87.Merging Overlapping Intervals 

88.Activity Selection Problem 

89.Job Sequencing Problem with Deadlines 

90.Introduction to Priority Queues using Binary Heaps 

91.Min Heap and Max Heap Implementation in C++ 

92.Min Heap and Max Heap Implementation in Java 

93.Heap Sort (Out-of-place and In-place implementation in C++ and C) 94.Check if given array represents min heap or not 

95.Convert Max Heap to Min Heap in linear time 

96.Find K’th largest element in an array 

97.Sort a K-Sorted Array 

98.Merge M sorted lists of variable length 

99.Find K’th smallest element in an array 

100.Find smallest range with at-least one element from each of the given lists 101.Merge M sorted lists each containing N elements 

102.Insertion sort | Iterative & Recursive 

103.Selection sort | Iterative & Recursive 

104.Bubble sort | Iterative & Recursive 

105.Merge Sort 

106.Quicksort 

107.Iterative Implementation of Quicksort 

108.Hybrid QuickSort 

109.Quicksort using Dutch National Flag Algorithm 

110.Quick Sort using Hoare’s Partitioning scheme 

111.External merge sort 

112.Custom Sort | Sort elements by their frequency and Index 

113.Custom Sort | Sort elements of the array by order of elements defined by the second array 

114.Inversion Count of an array 

115.Segregate positive and negative integers in linear time 116.Binary Search 

117.Ternary Search vs Binary search 

118.Interpolation search 

119.Exponential search 

120.Find number of rotations in a circularly sorted array 

121.Search an element in a circular sorted array 

122.Find first or last occurrence of a given number in a sorted array 123.Count occurrences of a number in a sorted array with duplicates 124.Find smallest missing element from a sorted array 

125.Find Floor and Ceil of a number in a sorted array 

126.Search in a nearly sorted array in O(logn) time 

127.Find number of 1’s in a sorted binary array 

128.Find the peak element in an array 

129.Maximum Sum Subarray using Divide & Conquer 

130.Find Minimum and Maximum element in an array using minimum comparisons 

131.Matrix Chain Multiplication 132.0–1 Knapsack problem 133.Maximize value of the expression 

134.Partition problem 

135.Subset sum problem 136.Minimum Sum Partition problem 137.Rod Cutting 

138.Coin change-making problem (unlimited supply of coins) 

139.Coin Change Problem (Total number of ways to get the denomination of coins) 

140.Longest alternating subsequence 

141.Combinations of words formed by replacing given numbers with corresponding alphabets 

142.Decode the given sequence to construct minimum number without repeated digits 

143.All combinations of elements satisfying given constraints 

144.Find Missing Term in a Sequence in log(n) time 

145.Print all distinct Subsets of a given Set 

146.Find Floor and Ceil of a number in a sorted array (Recursive solution) 147.Set both elements of a binary array to 0 in single line 

148.K-Partition Problem | Printing all Partitions 

149.3 Partition Problem 

150.3-partition problem extended | Print all partitions 

151.Iterative Merge Sort Algorithm (Bottom-up Merge Sort) 

152.Find two duplicate elements in an limited range array (using XOR) 153.Find missing number and duplicate elements in an array 

154.Find Minimum and Maximum element in an array by doing minimum comparisons 

155.Find Frequency of each element in a sorted array containing duplicates 156.Difference between Subarray, Subsequence and Subset 

Backtracking 

1.Print all possible solutions to N Queens problem 2.Print all Possible Knight’s Tours in a chessboard 3.Find Shortest Path in Maze 

4.Find Longest Possible Route in a Matrix 

5.Find path from source to destination in a matrix that satisfies given constraints 

6.Find total number of unique paths in a maze from source to destination 7.Print All Hamiltonian Path present in a graph 

8.Print all k-colorable configurations of the graph (Vertex coloring of graph) 9.Find all Permutations of a given string 

10.All combinations of elements satisfying given constraints 

11.Find all binary strings that can be formed from given wildcard pattern 12.K-Partition Problem | Printing all Partitions 

13.Magnet Puzzle 

14.Find ways to calculate a target from elements of specified array 15.Find minimum number possible by doing at-most K swaps 16.Determine if a pattern matches with a string or not 

Binary 

1.Bit Hacks  —  Part 1 (Basic) 

2.Bit Hacks  —  Part 2 (Playing with k’th bit) 

3.Bit Hacks  —  Part 3 (Playing with rightmost set bit of a number) 

4.Bit Hacks  —  Part 4 (Playing with letters of English alphabet) 

5.Bit Hacks  —  Part 5 (Find absolute value of an integer without branching) 

6.Bit Hacks  —  Part 6 (Random Problems) 

7.Brian Kernighan’s Algorithm to count set bits in an integer 

8.Compute parity of a number using lookup table 

9.Count set bits using lookup table 

10.Find the minimum or maximum of two integers without using branching 11.Multiply 16-bit integers using 8-bit multiplier 

12.Round up to the next highest power of 2 

13.Round up to the previous power of 2 

14.Swap individual bits at given position in an integer 

15.Check if given number is power of 4 or not 

16.Reverse Bits of a given Integer 

17.Find odd occurring element in an array in single traversal 

18.Find two odd occurring element in an array without using any extra space 19.Swap two bits at given position in an integer 

20.Add binary representation of two integers 

21.Swap Adjacent Bits of a Number 

22.Print all distinct Subsets of a given Set 

23.Perform Division of two numbers without using division operator (/) 24.Check if adjacent bits are set in binary representation of a given number 25.Conditionally negate a value without branching 

26.Find two duplicate elements in an limited range array (using XOR) 27.Find missing number and duplicate elements in an array 28.Check if given number is power of 8 or not 

29.Circular shift on binary representation of an integer by k positions 

30.Solve given set of problems without using multiplication or division operators 

31.Reverse Bits of an integer using lookup table 

32.Generate binary numbers between 1 to N 

33.Efficiently implement power function | Recursive and Iterative 

34.Find square of a number without using multiplication and division operator | 3 methods 

35.Generate power set of a given set 36.Huffman Coding 

37.Find all odd occurring elements in an array having limited range of elements 

Binary Tree 

1.Check if two given binary trees are identical or not | Iterative & Recursive 2.Calculate height of a binary tree | Iterative & Recursive 

3.Delete given Binary Tree | Iterative & Recursive 

4.Inorder Tree Traversal | Iterative & Recursive 

5.Preorder Tree Traversal | Iterative & Recursive 

6.Postorder Tree Traversal | Iterative & Recursive 

7.Level Order Traversal of Binary Tree 

8.Spiral Order Traversal of Binary Tree 

9.Reverse Level Order Traversal of Binary Tree 

10.Print all nodes of a given binary tree in specific order 11.Print left view of binary tree 

12.Print Bottom View of Binary Tree 

13.Print Top View of Binary Tree 

14.Find next node in same level for given node in a binary tree 15.Check if given binary tree is complete binary tree or not 16.Determine if given two nodes are cousins of each other 17.Print cousins of given node in a binary tree 

18.In-place convert given binary tree to its sum tree 

19.Check if given binary tree is a sum tree or not 

20.Combinations of words formed by replacing given numbers with corresponding alphabets 

21.Determine if given binary tree is a subtree of another binary tree or not 22.Find diameter of a binary tree 

23.Check if given binary Tree has symmetric structure or not 

24.Convert binary tree to its mirror 

25.Check if binary tree can be converted to another by doing any no. of swaps of left & right child 

26.Find Lowest Common Ancestor (LCA) of two nodes in a binary tree 27.Print all paths from root to leaf nodes in given binary tree 

28.Find ancestors of given node in a Binary Tree 

29.Find the distance between given pairs of nodes in a binary tree 30.Find Vertical Sum in a given Binary Tree 

31.Print nodes in vertical order of a given Binary Tree (Vertical Traversal) 32.Find the diagonal sum of given binary tree 

33.Print Diagonal Traversal of Binary Tree 

34.Print corner nodes of every level in binary tree 

35.In-place convert convert given Binary Tree to Doubly Linked List 36.Sink nodes containing zero to the bottom of the binary tree 37.Convert given binary tree to full tree by removing half nodes 

38.Truncate given binary tree to remove nodes which lie on a path having sum less than K 

39.Find maximum sum root-to-leaf path in a binary tree 

40.Check if given binary tree is height balanced or not 

41.Convert normal binary tree to Left-child right-sibling binary tree 42.Determine if given Binary Tree is a BST or not 

43.Convert a Binary Tree to BST by maintaining its original structure 44.Invert given Binary Tree | Recursive and Iterative solution 45.Print Right View of a Binary Tree 

46.Print leaf to root path for every leaf node in a binary tree 

47.Find maximum width of given binary tree 

48.Build Binary Tree from given Parent array 

49.C++ Program to Print Binary Tree Structure 

50.Find all nodes at given distance from leaf nodes in a binary tree 51.Count all subtrees having same value of nodes in a binary tree 

52.Find Maximum Difference Between a Node and its Descendants in a Binary Tree 

53.Construct a Binary Tree from Ancestor Matrix 

54.Calculate height of a binary tree with leaf nodes forming a circular doubly linked list 

BST 

1.Insertion in BST 

2.Search given key in BST 

3.Deletion from BST 

4.Construct balanced BST from given keys 

5.Determine if given Binary Tree is a BST or not 

6.Check if given keys represents same BSTs or not without building the BST 7.Find inorder predecessor for given key in a BST 

8.Find Lowest Common Ancestor (LCA) of two nodes in a Binary Search Tree 9.Find K’th smallest and K’th largest element in BST 

10.Floor and Ceil in a Binary Search Tree 

11.Find optimal cost to construct binary search tree 

12.Convert a Binary Tree to BST by maintaining its original structure 13.Remove nodes from BST that have keys outside the valid range 

14.Find a pair with given sum in a BST 

15.Find inorder successor for given key in a BST 

16.Replace every element of an array with the least greater element on its right 

Divide & Conquer 

1.Binary Search 

2.Find number of rotations in a circularly sorted array 

3.Search an element in a circular sorted array 

4.Find first or last occurrence of a given number in a sorted array 5.Count occurrences of a number in a sorted array with duplicates 6.Find smallest missing element from a sorted array 

7.Find Floor and Ceil of a number in a sorted array 

8.Search in a nearly sorted array in O(logn) time 

9.Find number of 1’s in a sorted binary array 

10.Find the peak element in an array 

11.Maximum Sum Subarray using Divide & Conquer 

12.Find Minimum and Maximum element in an array using minimum comparisons 

13.Efficiently implement power function | Recursive and Iterative 14.Find Missing Term in a Sequence in log(n) time 

15.Division of Two Numbers using Binary Search Algorithm 

16.Find Floor and Ceil of a number in a sorted array (Recursive solution) 

17.Find Minimum and Maximum element in an array by doing minimum comparisons 

18.Find Frequency of each element in a sorted array containing duplicates 19.Ternary Search vs Binary search 

20.Exponential search 

21.Interpolation search 

22.Merge Sort Algorithm 

23.Iterative Merge Sort Algorithm (Bottom-up Merge Sort) 

24.Merge Sort Algorithm for Singly Linked List 

25.Inversion Count of an array 

26.Quicksort Algorithm 

27.Iterative Implementation of Quicksort 28.Hybrid QuickSort 

29.Quicksort using Dutch National Flag Algorithm 30.Quick Sort using Hoare’s Partitioning scheme 

Dynamic Programming 

1.Introduction to Dynamic Programming 

2.Longest Common Subsequence | Introduction & LCS Length 3.Longest Common Subsequence | Space optimized version 4.Longest Common Subsequence of K-sequences 

5.Longest Common Subsequence | Finding all LCS 

6.Longest Common Substring problem 

7.Longest Palindromic Subsequence using Dynamic Programming 8.Longest Repeated Subsequence problem 

9.Implement Diff Utility 

10.Shortest Common Supersequence | Introduction & SCS Length 11.Shortest Common Supersequence | Finding all SCS 12.Shortest Common Supersequence | Using LCS 

13.Longest Increasing Subsequence using Dynamic Programming 14.Longest Bitonic Subsequence 

15.Increasing Subsequence with Maximum Sum 

16.The Levenshtein distance (Edit distance) problem 

17.Find size of largest square sub-matrix of 1’s present in given binary matrix 18.Matrix Chain Multiplication 

19.Find the minimum cost to reach last cell of the matrix from its first cell 20.Find longest sequence formed by adjacent numbers in the matrix 21.Count number of paths in a matrix with given cost to reach destination cell 22.0–1 Knapsack problem 

23.Maximize value of the expression 

24.Partition problem 

25.Subset sum problem 

26.Minimum Sum Partition problem 

27.Find all N-digit binary strings without any consecutive 1’s 

28.Rod Cutting 

29.Maximum Product Rod Cutting 

30.Coin change-making problem (unlimited supply of coins) 

31.Coin Change Problem  —  Find total number of ways to get the denomination of coins 

32.Total possible solutions to linear equation of k variables 33.Longest alternating subsequence 

34.Count number of times a pattern appears in given string as a subsequence 

35.Collect maximum points in a matrix by satisfying given constraints 36.Count total possible combinations of N-digit numbers in a mobile keypad 37.Find optimal cost to construct binary search tree 

38.Word Break Problem 

39.Word Break Problem | Using Trie Data Structure 

40.Determine Minimal Adjustment Cost of an Array 

41.Check if a string is K-Palindrome or not 

42.Wildcard Pattern Matching 

43.Find probability that a person is alive after taking N steps on the island 44.Calculate sum of all elements in a sub-matrix in constant time 

45.Find maximum sum K x K sub-matrix in a given M x N matrix 

46.Find maximum sum submatrix present in a given matrix 

47.Find maximum sum of subsequence with no adjacent elements 48.Maximum subarray problem (Kadane’s algorithm) 

49.Single-Source Shortest Paths—Bellman Ford Algorithm 

50.All-Pairs Shortest Paths—Floyd Warshall Algorithm 

51.Longest Decreasing Subsequence Problem 

52.Pots of Gold Game using Dynamic Programming 

53.Find minimum cuts needed for palindromic partition of a string 54.Maximum Length Snake Sequence 55.3 Partition Problem 56.Calculate size of the largest plus of 1’s in binary matrix 

57.Check if given string is interleaving of two other given strings 58.Longest Increasing Subsequence using LCS 

59.Determine negative-weight cycle in a graph 

Graphs 

1.Terminology and Representations of Graphs 

2.Graph Implementation using STL 

3.Graph Implementation in C++ without using STL 

4.Implement Graph Data Structure in C 

5.Graph Implementation in Java using Collections 

6.Breadth First Search (BFS) | Iterative & Recursive Implementation 7.Depth First Search (DFS) | Iterative & Recursive Implementation 8.Arrival and Departure Time of Vertices in DFS 

9.Types of edges involved in DFS and relation between them 10.Bipartite Graph 

11.Determine if a given graph is Bipartite Graph using DFS 12.Minimum number of throws required to win Snake and Ladder game 13.Topological Sorting in a DAG 

14.Kahn’s Topological Sort Algorithm 

15.Transitive Closure of a Graph 

16.Check if an undirected graph contains cycle or not 

17.Total paths in given digraph from given source to destination having exactly m edges 

18.Determine if an undirected graph is a Tree (Acyclic Connected Graph) 19.2-Edge Connectivity in the graph 

20.2-Vertex Connectivity in the graph 

21.Check if given digraph is a DAG (Directed Acyclic Graph) or not 22.Disjoint-Set Data Structure (Union-Find Algorithm) 

23.Chess Knight Problem  —  Find Shortest path from source to destination 24.Check if given Graph is Strongly Connected or not 

25.Check if given Graph is Strongly Connected or not using one DFS Traversal 

26.Union-Find Algorithm for Cycle Detection in undirected graph 27.Kruskal’s Algorithm for finding Minimum Spanning Tree 

28.Single-Source Shortest Paths—Dijkstra’s Algorithm 

29.Single-Source Shortest Paths—Bellman Ford Algorithm 

30.All-Pairs Shortest Paths—Floyd Warshall Algorithm 

31.Find Cost of Shortest Path in DAG using one pass of Bellman-Ford 32.Least Cost Path in Weighted Digraph using BFS 

33.Find maximum cost path in graph from given source to destination 34.Determine negative-weight cycle in a graph 

35.Print all k-colorable configurations of the graph (Vertex coloring of graph) 36.Print All Hamiltonian Path present in a graph 

37.Greedy coloring of graph 

Heap 

1.Introduction to Priority Queues using Binary Heaps 2.Min Heap and Max Heap Implementation in C++ 3.Min Heap and Max Heap Implementation in Java 4.Heap Sort 

5.Check if given array represents min heap or not 6.Convert Max Heap to Min Heap in linear time 7.Find K’th largest element in an array 

8.Sort a K-Sorted Array 

9.Merge M sorted lists of variable length 

10.Find K’th smallest element in an array 

11.Find smallest range with at-least one element from each of the given lists 12.Merge M sorted lists each containing N elements 

13.External merge sort 

14.Huffman Coding 

15.Find first k maximum occurring words in given set of strings 

16.Find first k non-repeating characters in a string in single traversal 

Linked List 

1.Introduction to Linked Lists 2.Linked List Implementation | Part 1 3.Linked List Implementation | Part 2 4.Static Linked List in C 

5.Clone given Linked List 

6.Delete Linked List 

7.Pop operation in linked list 

8.Insert given node into the correct sorted position in the given sorted linked list 

9.Given a linked list, change it to be in sorted order 

10.Split the nodes of the given linked list into front and back halves 11.Remove duplicates from a sorted linked list 

12.Move front node of the given list to the front of the another list 13.Move even nodes to the end of the list in reverse order 

14.Split given linked list into two lists where each list containing alternating elements from it 

15.Construct a linked list by merging alternate nodes of two given lists 16.Merge given sorted linked lists into one 

17.Merge Sort Algorithm for Singly Linked List 

18.Intersection of two given sorted linked lists 

19.Reverse linked list | Part 1 (Iterative Solution) 

20.Reverse linked list | Part 2 (Recursive Solution) 

21.Reverse every group of k nodes in given linked list 

22.Find K’th node from the end in a linked list 

23.Merge alternate nodes of two linked lists into the first list 

24.Merge two sorted linked lists from their end 

25.Delete every N nodes in a linked list after skipping M nodes 26.Rearrange linked list in specific manner in linear time 

27.Check if linked list is palindrome or not 

28.Move last node to front in a given Linked List 

29.Rearrange the linked list in specific manner 

30.Detect Cycle in a linked list (Floyd’s Cycle Detection Algorithm) 

31.Sort linked list containing 0’s, 1’s and 2’s 

32.Stack Implementation using Linked List 

33.Queue Implementation using Linked List 

34.Remove duplicates from a linked list 

35.Rearrange the linked list so that it has alternating high, low values 36.Rearrange a Linked List by Separating Odd Nodes from the Even Ones 

37.Calculate height of a binary tree with leaf nodes forming a circular doubly linked list 

Matrix 

1.Print Matrix in Spiral Order 

2.Create Spiral Matrix from given array 3.Shift all matrix elements by 1 in Spiral Order 

4.Find Shortest path from source to destination in a matrix that satisfies given constraints 

5.Change all elements of row i and column j in a matrix to 0 if cell (i, j) has value 0 

6.Print diagonal elements of the matrix having positive slope 

7.Find all paths from first cell to last cell of a matrix 

8.Replace all occurrences of 0 that are not surrounded by 1 in a binary matrix 9.In-place rotate the matrix by 90 degrees in clock-wise direction 

10.Count negative elements present in sorted matrix in linear time 

11.Report all occurrences of an element in row wise and column wise sorted matrix in linear time 

12.Calculate sum of all elements in a sub-matrix in constant time 

13.Find maximum sum K x K sub-matrix in a given M x N matrix 

14.Find maximum sum submatrix present in a given matrix 

15.Find probability that a person is alive after taking N steps on the island 16.Count the number of islands 

17.Flood fill Algorithm 

18.Find shortest safe route in a field with sensors present 

19.Find all occurrences of given string in a character matrix 

20.Shortest path in a Maze | Lee algorithm 

21.Check if given matrix is Toeplitz matrix or not 

22.In-place rotate the matrix by 180 degrees 

23.Fill Binary Matrix with Alternating Rectangles of 0 and 1 

24.Find all common elements present in every row of given matrix 25.Construct a Binary Tree from Ancestor Matrix 

26.Find common elements present in all rows of a matrix 

27.Travelling Salesman Problem using Branch and Bound 

28.Collect maximum points in a matrix by satisfying given constraints 29.Count number of paths in a matrix with given cost to reach destination cell 30.Find longest sequence formed by adjacent numbers in the matrix 

31.Find the minimum cost to reach last cell of the matrix from its first cell 32.Matrix Chain Multiplication 

33.Find size of largest square sub-matrix of 1’s present in given binary matrix 34.Chess Knight Problem  —  Find Shortest path from source to destination 

35.Find Duplicate rows in a binary matrix 

36.Print all possible solutions to N Queens problem 

37.Print all Possible Knight’s Tours in a chessboard 

38.Find Shortest Path in Maze 

39.Find Longest Possible Route in a Matrix 

40.Calculate size of the largest plus of 1’s in binary matrix 

41.Find the maximum value of M[c][d]  —  M[a][b] over all choices of indexes 42.Find shortest distance of every cell from landmine in a Maze 

43.Find shortest route in a device to construct the given string 

Queue 

1.Queue Implementation 

2.Queue Implementation using Linked List 

3.Chess Knight Problem  —  Find Shortest path from source to destination 4.Shortest path in a Maze | Lee algorithm 

5.Find shortest safe route in a field with sensors present 

6.Flood fill Algorithm 

7.Count the number of islands 

8.Find Shortest path from source to destination in a matrix that satisfies given constraints 

9.Generate binary numbers between 1 to N 

10.Calculate height of a binary tree | Iterative & Recursive 11.Delete given Binary Tree | Iterative & Recursive 

12.Level Order Traversal of Binary Tree 

13.Spiral Order Traversal of Binary Tree 

14.Reverse Level Order Traversal of Binary Tree 

15.Print all nodes of a given binary tree in specific order 16.Print left view of binary tree 

17.Find next node in same level for given node in a binary tree 18.Check if given binary tree is complete binary tree or not 19.Print Diagonal Traversal of Binary Tree 

20.Print corner nodes of every level in binary tree 

21.Breadth First Search (BFS) | Iterative & Recursive Implementation 22.Minimum number of throws required to win Snake and Ladder game 23.Check if an undirected graph contains cycle or not 

24.Invert given Binary Tree | Recursive and Iterative solution 

25.Find maximum cost path in graph from given source to destination 26.Find shortest distance of every cell from landmine in a Maze 

Sorting 

1.Insertion sort | Iterative & Recursive 

2.Selection sort | Iterative & Recursive 

3.Bubble sort | Iterative & Recursive 

4.Merge Sort Algorithm 

5.Iterative Merge Sort Algorithm (Bottom-up Merge Sort) 6.Quicksort Algorithm 

7.Iterative Implementation of Quicksort 

8.Hybrid QuickSort 

9.Quicksort using Dutch National Flag Algorithm 10.Quick Sort using Hoare’s Partitioning scheme 11.External merge sort 

12.Counting Sort Algorithm 

13.Custom Sort | Sort elements by their frequency and Index 

14.Custom Sort | Sort elements of the array by order of elements defined by the second array 

15.Inversion Count of an array 

16.Segregate positive and negative integers in linear time 17.Efficiently Sort an Array with many Duplicated Values 

18.Find the smallest window in array sorting which will make the entire array sorted 

19.Find largest number possible from set of given numbers 20.Move all zeros present in the array to the end 

21.Sort binary array in linear time 

22.Sort linked list containing 0’s, 1’s and 2’s 

23.Merge Sort Algorithm for Singly Linked List 

24.Group anagrams together from given list of words 25.Activity Selection Problem 

26.Lexicographic sorting of given set of keys 

27.Heap Sort 

28.Merge M sorted lists of variable length 

29.Merge M sorted lists each containing N elements 30.Find all palindromic permutations of a string 

31.Find all lexicographically next permutations of a string sorted in ascending order 

32.Merge two sorted linked lists from their end 

33.Sort an array containing 0’s, 1’s and 2’s (Dutch national flag problem) 34.Find pair with given sum in the array 

35.Inplace merge two sorted arrays 

36.Merge two arrays by satisfying given constraints 

37.Find maximum product of two integers in an array 

38.Find all distinct combinations of given length 

39.Find all distinct combinations of given length with repetition allowed 40.Merging Overlapping Intervals 

41.Print all quadruplets with given sum | 4-sum problem extended 42.4 sum problem | Quadruplets with given sum 43.Find two numbers with maximum sum formed by array digits 

44.Find a Triplet having Maximum Product in an Array 

45.Find Minimum Product among all Combinations of Triplets in an Array 46.Find all distinct combinations of given length  —  Part 2 

47.Find the surpasser count for each element of an array 

Stack 

1.Stack Implementation 

2.Stack Implementation using Linked List 

3.Check if given expression is balanced expression or not 4.Find duplicate parenthesis in an expression 

5.Evaluate given postfix expression 

6.Decode the given sequence to construct minimum number without repeated digits

7.Inorder Tree Traversal | Iterative & Recursive 

8.Preorder Tree Traversal | Iterative & Recursive 

9.Postorder Tree Traversal | Iterative & Recursive 

10.Find ancestors of given node in a Binary Tree 

11.Check if two given binary trees are identical or not | Iterative & Recursive 

12.Reverse given text without reversing the individual words 

13.Find all binary strings that can be formed from given wildcard pattern 14.Iterative Implementation of Quicksort 

15.Depth First Search (DFS) | Iterative & Recursive Implementation 16.Invert given Binary Tree | Recursive and Iterative solution 

17.Print leaf to root path for every leaf node in a binary tree 

String 

1.Check if given string is a rotated palindrome or not 

2.Longest Palindromic Substring (Non-DP Space Optimized Solution) 3.Check if repeated subsequence is present in the string or not 

4.Check if strings can be derived from each other by circularly rotating them 5.Check if given set of moves is circular or not 

6.Convert given number into corresponding excel column name 7.Determine if two strings are anagram or not 

8.Find all binary strings that can be formed from given wildcard pattern 9.Find all interleavings of given strings 

10.Isomorphic Strings 

11.Find all possible palindromic substrings in a string 

12.Find all possible combinations of words formed from mobile keypad 

13.Find all possible combinations by replacing given digits with characters of the corresponding list 

14.Find all words from given list that follows same order of characters as given pattern 

15.Find first k non-repeating characters in a string in single traversal 

16.Group anagrams together from given list of words 

17.Introduction to Pattern Matching 

18.Inplace remove all occurrences of ‘AB’ and ‘C’ from the string 

19.Longest even length palidromic sum substring 

20.Print string in zig-zag form in k rows 

21.Reverse given text without reversing the individual words 

22.Run Length Encoding (RLE) data compression algorithm 

23.Validate an IP address 

24.Find the longest substring of given string containing k distinct characters 25.Find all palindromic permutations of a string 

26.Find all substrings of a string that are permutation of a given string 27.Find the longest substring of given string containing all distinct characters 28.Find all Permutations of a given string 

29.Iterative Approach to find Permutations of a String in C++ and Java 30.Generate all Permutations of a String in Java | Recursive & Iterative 

31.Find all lexicographically next permutations of a string sorted in ascending order 

32.Find Lexicographically minimal string rotation 

33.Find all strings of given length containing balanced parentheses 

34.Find all N-digit strictly increasing numbers (Bottom-Up and Top-Down Approach) 

35.Find all N-digit binary numbers having more 1’s than 0’s for any prefix 36.Find all N-digit numbers with given sum of digits 

37.Find all N-digit binary numbers with k-bits set where k ranges from 1 to N 

38.Generate binary numbers between 1 to N 

39.Find all combinations of non-overlapping substrings of a string 40.Check if given sentence is syntactically correct or not 

41.Calculate rank of given string among all its lexicographically sorted permutations 

42.Find all Lexicographic Permutations of a String 

43.Find all N-digit binary numbers with equal sum of bits in its two halves 44.Check if given string is interleaving of two other given strings 45.Difference between Subarray, Subsequence and Subset 46.std::next_permutation | Overview & Implementation in C++ 47.std::prev_permutation | Overview & Implementation in C++ 48.Implementation of KMP Algorithm in C, C++ and Java 

49.Reverse String without using Recursion 

50.Reverse given string using Recursion 

51.Reverse a String in Java in 10 different ways 

52.Determine if a given string is palindrome or not 

53.In-place remove all adjacent duplicates from the given string 

54.Find the minimum number of inversions needed to make the given expression balanced 

55.Replace all non-overlapping occurrences of the pattern 

56.Construct the longest palindrome by shuffling or deleting characters from a string

57.Determine if characters of a String follows a specified order or not

58.Print all combinations of phrases that can be formed by picking words from each of the given lists

59.Remove all extra spaces from a string 

60.Break a string into all possible combinations of non-overlapping substrings 61.Remove adjacent duplicate characters from a string 

62.Combinations of words formed by replacing given numbers with corresponding alphabets 

63.Word Break Problem 64.Wildcard Pattern Matching 

65.Count number of times a pattern appears in given string as a subsequence 

66.The Levenshtein distance (Edit distance) problem 

67.Longest Common Subsequence | Introduction & LCS Length 68.Longest Common Subsequence | Space optimized version 69.Longest Common Subsequence of K-sequences 

70.Longest Common Subsequence | Finding all LCS 

71.Longest Repeated Subsequence problem 

72.Longest Palindromic Subsequence using Dynamic Programming 73.Longest Common Substring problem 

74.Shortest Common Supersequence | Introduction & SCS Length 75.Shortest Common Supersequence | Finding all SCS 76.Shortest Common Supersequence | Using LCS 

77.Implement Diff Utility 

78.Word Break Problem | Using Trie Data Structure 

79.Find minimum cuts needed for palindromic partition of a string 80.Check if a string is K-Palindrome or not 

81.Find shortest route in a device to construct the given string 82.Find minimum number possible by doing at-most K swaps 83.Determine if a pattern matches with a string or not 

Trie 

1.Trie Implementation | Insert, Search and Delete 

2.Memory efficient Trie Implementation using Map | Insert, Search and Delete 3.C++ Implementation of Trie Data Structure 

4.Longest Common Prefix in given set of strings (using Trie) 

5.Lexicographic sorting of given set of keys 

6.Find maximum occurring word in given set of strings 

7.Find first k maximum occurring words in given set of strings 

8.Find Duplicate rows in a binary matrix 

9.Word Break Problem | Using Trie Data Structure 

Greedy 

1.Activity Selection Problem 

2.Huffman Coding 

3.Shortest Superstring Problem 

4.Job Sequencing Problem with Deadlines 

5.Greedy coloring of graph 

6.Kruskal’s Algorithm for finding Minimum Spanning Tree 7.Single-Source Shortest Paths—Dijkstra’s Algorithm 

Puzzles 

1.Clock angle problem  —  Find angle between hour and minute hand 2.Add two numbers without using addition operator | 4 methods 3.Generate power set of a given set 

4.Implement power function without using multiplication and division operators 

5.Print all numbers between 1 to N without using semicolon 6.Swap two numbers without using third variable | 5 methods 7.Determine the if condition to print specific output 

8.Find maximum, minimum of three numbers without using conditional statement and ternary operator | 4 methods 

9.Find numbers represented as sum of two cubes for two different pairs 10.Print “Hello World” with empty main() function | 3 methods 

11.Tower of Hanoi Problem 

12.Print all numbers between 1 to N without using any loop | 4 methods 13.Print a semicolon without using semicolon anywhere in the program 14.Multiply two numbers without using multiplication operator or loops 

15.Find square of a number without using multiplication and division operator | 3 methods 

16.Find if a number is even or odd without using any conditional statement 17.Set both elements of a binary array to 0 in single line 

18.Find minimum number without using conditional statement or ternary operator 

19.Perform Division of two numbers without using division operator (/) 20.Generate 0 and 1 with 75% and 25% Probability 

21.Generate Desired Random Numbers With Equal Probability 

22.Return 0, 1 and 2 with equal Probability using the specified function 23.Generate Fair Results from a Biased Coin

24.Generate numbers from 1 to 7 with equal probability using specified function

25.Implement Ternary Operator Without Using Conditional Expressions

26.Determine if two integers are equal without using comparison and arithmetic operators

27.Return 0 and 1 with equal Probability using the specified function 28.Generate Random Input from an Array according to given Probabilities 29.Generate Fair Results from a Biased Coin

30.Magnet Puzzle