DSA Cracker Sheet by Love Babbar

Link to the video describing this sheet.

Link to the original sheet.

Here's a collage of awesome DSA crackers.

-	-	-	-	-
Arrays	Matrix	String	Searching & Sorting	Linked List
Binary Trees	Binary Search Trees	Greedy	BackTracking	Stacks & Queues
Heap	Graph	Trie	Dynamic Programming	Bit Manipulation

Arrays

S. No.	Problem	Reference	C++	Java	Python	Other languages
01	Reverse the array	GeeksForGeeks	0	1	0	-
02	Find the maximum and minimum element in an array	GeeksForGeeks	0	1	0	-
03	Find the "Kth" max and min element of an array	GeeksForGeeks	0	1	0	-
04	Given an array which consists of only 0, 1 and 2. Sort the array without using any sorting algo	GeeksForGeeks	0	1	0	-
05	Move all the negative elements to one side of the array	GeeksForGeeks	0	1	0	-
06	Find the Union and Intersection of the two sorted arrays	GeeksForGeeks	0	1	0	-
07	Write a program to cyclically rotate an array by one.	GeeksForGeeks	0	1	0	-
08	Find Largest sum contiguous Subarray [V. IMP]	GeeksForGeeks	0	1	0	-
09	Minimise the maximum difference between heights [V.IMP]	GeeksForGeeks	0	1	0	-
10	Minimum no. of Jumps to reach end of an array	GeeksForGeeks	0	0	0	-
11	Find duplicate in an array of N+1 Integers	Leetcode	0	0	0	-
12	Merge 2 sorted arrays without using Extra space	GeeksForGeeks	0	0	0	-
13	Kadane's Algo [V.V.V.V.V IMP]	GeeksForGeeks	0	0	0	-
14	Merge Intervals	Leetcode	0	0	0	-
15	Next Permutation	Leetcode	0	0	0	-
16	Count Inversion	GeeksForGeeks	0	0	0	-
17	Best time to buy and Sell stock	Leetcode	0	0	0	-
18	Find all pairs on integer array whose sum is equal to given number	GeeksForGeeks	0	0	0	-
19	Find common elements In 3 sorted arrays	GeeksForGeeks	0	0	0	-
20	Rearrange the array in alternating positive and negative items with O(1) extra space	GeeksForGeeks	0	0	0	-
21	Find if there is any subarray with sum equal to 0	GeeksForGeeks	0	0	0	-
22	Find factorial of a large number	GeeksForGeeks	0	0	0	-
23	Find maximum product subarray	GeeksForGeeks	0	0	0	-
24	Find longest consecutive subsequence	GeeksForGeeks	0	0	0	-
25	Given an array of size n and a number k, fin all elements that appear more than " n/k " times	GeeksForGeeks	0	0	0	-
26	Maximum profit by buying and selling a share atmost twice	GeeksForGeeks	0	0	0	-
27	Find whether an array is a subset of another array	GeeksForGeeks	0	0	0	-
28	Find the triplet that sum to a given value	GeeksForGeeks	0	0	0	-
29	Trapping Rain water problem	GeeksForGeeks	0	0	0	-
30	Chocolate Distribution problem	GeeksForGeeks	0	0	0	-
31	Smallest Subarray with sum greater than a given value	GeeksForGeeks	0	0	0	-
32	Three way partitioning of an array around a given value	GeeksForGeeks	0	0	0	-
33	Minimum swaps required bring elements less equal K together	GeeksForGeeks	0	0	0	-
34	Minimum no. of operations required to make an array palindrome	GeeksForGeeks	0	0	0	-
35	Median of 2 sorted arrays of equal size	GeeksForGeeks	0	0	0	-
36	Median of 2 sorted arrays of different size	GeeksForGeeks	0	0	0	-

Matrix

S. No.	Problem	Reference	C++	Java	Python	Other languages
37	Spiral traversal on a Matrix	GeeksForGeeks	0	0	0	-
38	Search an element in a matrix	Leetcode	0	0	0	-
39	Find median in a row wise sorted matrix	GeeksForGeeks	0	0	0	-
40	Find row with maximum no. of 1's	GeeksForGeeks	0	0	0	-
41	Print elements in sorted order using row-column wise sorted matrix	GeeksForGeeks	0	0	0	-
42	Maximum size rectangle	GeeksForGeeks	0	0	0	-
43	Find a specific pair in matrix	GeeksForGeeks	0	0	0	-
44	Rotate matrix by 90 degrees	GeeksForGeeks	0	0	0	-
45	Kth smallest element in a row-cpumn wise sorted matrix	GeeksForGeeks	0	0	0	-
46	Common elements in all rows of a given matrix	GeeksForGeeks	0	0	0	-

String

S. No.	Problem	Reference	C++	Java	Python	Other languages
47	Reverse a String	Leetcode	0	0	0	-
48	Check whether a String is Palindrome or not	GeeksForGeeks	0	0	0	-
49	Find Duplicate characters in a string	GeeksForGeeks	0	0	0	-
50	Why strings are immutable in Java?	GeeksForGeeks	0	0	0	-
51	Write a Code to check whether one string is a rotation of another	GeeksForGeeks	0	0	0	-
52	Write a Program to check whether a string is a valid shuffle of two strings or not	GeeksForGeeks	0	0	0	-
53	Count and Say problem	Leetcode	0	0	0	-
54	Write a program to find the longest Palindrome in a string.[ Longest palindromic Substring]	GeeksForGeeks	0	0	0	-
55	Find Longest Recurring Subsequence in String	GeeksForGeeks	0	0	0	-
56	Print all Subsequences of a string	GeeksForGeeks	0	0	0	-
57	Print all the permutations of the given string	GeeksForGeeks	0	0	0	-
58	Split the Binary string into two substring with equal 0’s and 1’s	GeeksForGeeks	0	0	0	-
59	Word Wrap Problem [VERY IMP]	GeeksForGeeks	0	0	0	-
60	EDIT Distance [Very Imp]	GeeksForGeeks	0	0	0	-
61	Find next greater number with same set of digits. [Very Very IMP]	GeeksForGeeks	0	0	0	-
62	Balanced Parenthesis problem.[Imp]	GeeksForGeeks	0	0	0	-
63	Word break Problem[ Very Imp]	GeeksForGeeks	0	0	0	-
64	Rabin Karp Algo	GeeksForGeeks	0	0	0	-
65	KMP Algo	GeeksForGeeks	0	0	0	-
66	Convert a Sentence into its equivalent mobile numeric keypad sequence	GeeksForGeeks	0	0	0	-
67	Minimum number of bracket reversals needed to make an expression balanced	GeeksForGeeks	0	0	0	-
68	Count All Palindromic Subsequence in a given String	GeeksForGeeks	0	0	0	-
69	Count of number of given string in 2D character array	GeeksForGeeks	0	0	0	-
70	Search a Word in a 2D Grid of characters	GeeksForGeeks	0	0	0	-
71	Boyer Moore Algorithm for Pattern Searching	GeeksForGeeks	0	0	0	-
72	Converting Roman Numerals to Decimal	GeeksForGeeks	0	0	0	-
73	Longest Common Prefix	LeetCode	0	0	0	-
74	Number of flips to make binary string alternate	GeeksForGeeks	0	0	0	-
75	Find the first repeated word in string	GeeksForGeeks	0	0	0	-
76	Minimum number of swaps for bracket balancing	GeeksForGeeks	0	0	0	-
77	Find the longest common subsequence between two strings	GeeksForGeeks	0	0	0	-
78	Program to generate all possible valid IP addresses from given string	GeeksForGeeks	0	0	0	-
79	Write a program to find the smallest window that contains all characters of string itself	GeeksForGeeks	0	0	0	-
80	Rearrange characters in a string such that no two adjacent are same	GeeksForGeeks	0	0	0	-
81	Minimum characters to be added at front to make string palindrome	GeeksForGeeks	0	0	0	-
82	Given a sequence of words, print all anagrams together	GeeksForGeeks	0	0	0	-
83	Find the smallest window in a string containing all characters of another string	GeeksForGeeks	0	0	0	-
84	Recursively remove all adjacent duplicates	GeeksForGeeks	0	0	0	-
85	String matching where one string contains wildcard characters	GeeksForGeeks	0	0	0	-
86	Function to find Number of customers who could not get a computer	GeeksForGeeks	0	0	0	-
87	Transform One String to Another using Minimum Number of Given Operation	GeeksForGeeks	0	0	0	-
88	Check if two given strings are isomorphic to each other	GeeksForGeeks	0	0	0	-
89	Recursively print all sentences that can be formed from list of word lists	GeeksForGeeks	0	0	0	-

Searching & Sorting

S. No.	Problem	Reference	C++	Java	Python	Other languages
90	Find first and last positions of an element in a sorted array	GeeksForGeeks	0	0	0	-
91	Find a Fixed Point (Value equal to index) in a given array	GeeksForGeeks	0	0	0	-
92	Search in a rotated sorted array	LeetCode	0	0	0	-
93	Square root of an integer	GeeksForGeeks	0	0	0	-
94	Maximum and minimum of an array using minimum number of comparisons	GeeksForGeeks	0	0	0	-
95	Optimum location of point to minimize total distance	GeeksForGeeks	0	0	0	-
96	Find the repeating and the missing	GeeksForGeeks	0	0	0	-
97	Find majority element	GeeksForGeeks	0	0	0	-
98	Searching in an array where adjacent differ by at most k	GeeksForGeeks	0	0	0	-
99	Find a pair with a given difference	GeeksForGeeks	0	0	0	-
100	Find four elements that sum to a given value	GeeksForGeeks	0	0	0	-
101	Maximum sum such that no 2 elements are adjacent	GeeksForGeeks	0	0	0	-
102	Count triplet with sum smaller than a given value	GeeksForGeeks	0	0	0	-
103	Merge 2 sorted arrays	GeeksForGeeks	0	0	0	-
104	Print all subarrays with 0 sum	GeeksForGeeks	0	0	0	-
105	Product array Puzzle	GeeksForGeeks	0	0	0	-
106	Sort array according to count of set bits	GeeksForGeeks	0	0	0	-
107	Minimum no. of swaps required to sort the array	GeeksForGeeks	0	0	0	-
108	Bishu and Soldiers	HackerEarth	0	0	0	-
109	Rasta and Kheshtak	HackerEarth	0	0	0	-
110	Kth smallest number again	HackerEarth	0	0	0	-
111	Find pivot element in a sorted array	TheoryofProgramming	0	0	0	-
112	K-th Element of Two Sorted Arrays	GeeksForGeeks	0	0	0	-
113	Aggressive cows	SPOJ	0	0	0	-
114	Book Allocation Problem	GeeksForGeeks	0	0	0	-
115	EKOSPOJ:	SPOJ	0	0	0	-
116	Job Scheduling Algo	GeeksForGeeks	0	0	0	-
117	Missing Number in AP	GeeksForGeeks	0	0	0	-
118	Smallest number with atleastn trailing zeroes infactorial	GeeksForGeeks	0	0	0	-
119	Painters Partition Problem:	GeeksForGeeks	0	0	0	-
120	ROTI-Prata SPOJ	SPOJ	0	0	0	-
121	DoubleHelix SPOJ	SPOJ	0	0	0	-
122	Subset Sums	SPOJ	0	0	0	-
123	Find the inversion count	GeeksForGeeks	0	0	0	-
124	Implement Merge-sort in-place	GeeksForGeeks	0	0	0	-
125	Partitioning and Sorting Arrays with Many Repeated Entries	Bealdung	0	0	0	-

LinkedList

S. No.	Problem	Reference	C++	Java	Python	Other languages
126	Write a Program to reverse the Linked List. (Both Iterative and recursive)	GeeksForGeeks	0	0	0	-
127	Reverse a Linked List in group of Given Size. [Very Imp]	GeeksForGeeks	0	0	0	-
128	Write a program to Remove loop in a linked list	GeeksForGeeks	0	0	0	-
129	Write a program to Delete loop in a linked list	GeeksForGeeks	0	0	0	-
130	Find the starting point of the loop	GeeksForGeeks	0	0	0	-
131	Remove Duplicates in a sorted Linked List	GeeksForGeeks	0	0	0	-
132	Remove Duplicates in a Un-sorted Linked List	GeeksForGeeks	0	0	0	-
133	Write a Program to Move the last element to Front in a Linked List	GeeksForGeeks	0	0	0	-
134	Add “1” to a number represented as a Linked List	GeeksForGeeks	0	0	0	-
135	Add two numbers represented by linked lists	GeeksForGeeks	0	0	0	-
136	Intersection of two Sorted Linked List	GeeksForGeeks	0	0	0	-
137	Intersection Point of two Linked Lists	GeeksForGeeks	0	0	0	-
138	Merge Sort For Linked lists.[Very Important]	GeeksForGeeks	0	0	0	-
139	Quicksort for Linked Lists.[Very Important]	GeeksForGeeks	0	0	0	-
140	Find the middle Element of a linked list	LeetCode	0	0	0	-
141	Check if a linked list is a circular linked list	GeeksForGeeks	0	0	0	-
142	Split a Circular linked list into two halves	GeeksForGeeks	0	0	0	-
143	Write a Program to check whether the Singly Linked list is a palindrome or not	GeeksForGeeks	0	0	0	-
144	Deletion from a Circular Linked List	GeeksForGeeks	0	0	0	-
145	Reverse a Doubly Linked list	GeeksForGeeks	0	0	0	-
146	Find pairs with a given sum in a DLL	GeeksForGeeks	0	0	0	-
147	Count triplets in a sorted DLL whose sum is equal to given value “X”	GeeksForGeeks	0	0	0	-
148	Sort a “k”sorted Doubly Linked list.[Very IMP]	GeeksForGeeks	0	0	0	-
149	Rotate DoublyLinked list by N nodes	GeeksForGeeks	0	0	0	-
150	Rotate a Doubly Linked list in group of Given Size.[Very IMP]	GeeksForGeeks	0	0	0	-
151	Can we reverse a linked list in less than O(n) ?	GeeksForGeeks	0	0	0	-
152	Why Quicksort is preferred for. Arrays and Merge Sort for LinkedLists ?	GeeksForGeeks	0	0	0	-
153	Flatten a Linked List	GeeksForGeeks	0	0	0	-
154	Sort a LL of 0's, 1's and 2's	GeeksForGeeks	0	0	0	-
155	Clone a linked list with next and random pointer	GeeksForGeeks	0	0	0	-
156	Merge K sorted Linked list	GeeksForGeeks	0	0	0	-
157	Multiply 2 no. represented by LL	GeeksForGeeks	0	0	0	-
158	Delete nodes which have a greater value on right side	GeeksForGeeks	0	0	0	-
159	Segregate even and odd nodes in a Linked List	GeeksForGeeks	0	0	0	-
160	Program for n’th node from the end of a Linked List	GeeksForGeeks	0	0	0	-
161	Find the first non-repeating character from a stream of characters	GeeksForGeeks	0	0	0	-

Binary Trees

S. No.	Problem	Reference	C++	Java	Python	Other languages
162	Level order traversal	GeeksForGeeks	0	0	0	-
163	Reverse Level Order traversal	GeeksForGeeks	0	0	0	-
164	Height of a tree	GeeksForGeeks	0	0	0	-
165	Diameter of a tree	GeeksForGeeks	0	0	0	-
166	Mirror of a tree	GeeksForGeeks	0	0	0	-
167	Inorder Traversal of a tree both using recursion and Iteration	TechieDelight	0	0	0	-
168	Preorder Traversal of a tree both using recursion and Iteration	TechieDelight	0	0	0	-
169	Postorder Traversal of a tree both using recursion and Iteration	TechieDelight	0	0	0	-
170	Left View of a tree	GeeksForGeeks	0	0	0	-
171	Right View of Tree	GeeksForGeeks	0	0	0	-
172	Top View of a tree	GeeksForGeeks	0	0	0	-
173	Bottom View of a tree	GeeksForGeeks	0	0	0	-
174	Zig-Zag traversal of a binary tree	GeeksForGeeks	0	0	0	-
175	Check if a tree is balanced or not	GeeksForGeeks	0	0	0	-
176	Diagnol Traversal of a Binary tree	GeeksForGeeks	0	0	0	-
177	Boundary traversal of a Binary tree	GeeksForGeeks	0	0	0	-
178	Construct Binary Tree from String with Bracket Representation	GeeksForGeeks	0	0	0	-
179	Convert Binary tree into Doubly Linked List	GeeksForGeeks	0	0	0	-
180	Convert Binary tree into Sum tree	GeeksForGeeks	0	0	0	-
181	Construct Binary tree from Inorder and preorder traversal	GeeksForGeeks	0	0	0	-
182	Find minimum swaps required to convert a Binary tree into BST	GeeksForGeeks	0	0	0	-
183	Check if Binary tree is Sum tree or not	GeeksForGeeks	0	0	0	-
184	Check if all leaf nodes are at same level or not	GeeksForGeeks	0	0	0	-
185	Check if a Binary Tree contains duplicate subtrees of size 2 or more [ IMP ]	GeeksForGeeks	0	0	0	-
186	Check if 2 trees are mirror or not	GeeksForGeeks	0	0	0	-
187	Sum of Nodes on the Longest path from root to leaf node	GeeksForGeeks	0	0	0	-
188	Check if given graph is tree or not. [ IMP ]	GeeksForGeeks	0	0	0	-
189	Find Largest subtree sum in a tree	GeeksForGeeks	0	0	0	-
190	Maximum Sum of nodes in Binary tree such that no two are adjacent	GeeksForGeeks	0	0	0	-
191	Print all "K" Sum paths in a Binary tree	GeeksForGeeks	0	0	0	-
192	Find LCA in a Binary tree	GeeksForGeeks	0	0	0	-
193	Find distance between 2 nodes in a Binary tree	GeeksForGeeks	0	0	0	-
194	Kth Ancestor of node in a Binary tree	GeeksForGeeks	0	0	0	-
195	Find all Duplicate subtrees in a Binary tree [ IMP ]	[GeeksForGeeks]https://practice.geeksforgeeks.org/problems/duplicate-subtrees/1)	0	0	0	-
196	Tree Isomorphism Problem	GeeksForGeeks	0	0	0	-

Binary Search Trees

S. No.	Problem	Reference	C++	Java	Python	Other languages
197	Find a value in a BST	GeeksForGeeks	0	0	0	-
198	Deletion of a node in a BST	LeetCode	0	0	0	-
199	Find min and max value in a BST	GeeksForGeeks	0	0	0	-
200	Find inorder successor and inorder predecessor in a BST	GeeksForGeeks	0	0	0	-
201	Check if a tree is a BST or not	GeeksForGeeks	0	0	0	-
202	Populate Inorder successor of all nodes	GeeksForGeeks	0	0	0	-
203	Find LCA of 2 nodes in a BST	GeeksForGeeks	0	0	0	-
204	Construct BST from preorder traversal	GeeksForGeeks	0	0	0	-
205	Convert Binary tree into BST	GeeksForGeeks	0	0	0	-
206	Convert a normal BST into a Balanced BST	GeeksForGeeks	0	0	0	-
207	Merge two BST [ V.V.V>IMP ]	GeeksForGeeks	0	0	0	-
208	Find Kth largest element in a BST	GeeksForGeeks	0	0	0	-
209	Find Kth smallest element in a BST	GeeksForGeeks	0	0	0	-
210	Count pairs from 2 BST whose sum is equal to given value "X"	GeeksForGeeks	0	0	0	-
211	Find the median of BST in O(n) time and O(1) space	GeeksForGeeks	0	0	0	-
212	Count BST ndoes that lie in a given range	GeeksForGeeks	0	0	0	-
213	Replace every element with the least greater element on its right	GeeksForGeeks	0	0	0	-
214	Given "n" appointments, find the conflicting appointments	GeeksForGeeks	0	0	0	-
215	Check preorder is valid or not	GeeksForGeeks	0	0	0	-
216	Check whether BST contains Dead end	GeeksForGeeks	0	0	0	-
217	Largest BST in a Binary Tree [ V.V.V.V.V IMP ]	GeeksForGeeks	0	0	0	-
218	Flatten BST to sorted list	GeeksForGeeks	0	0	0	-

Greedy

S. No.	Problem	Reference	C++	Java	Python	Other languages
219	Activity Selection Problem	GeeksForGeeks	0	0	0	-
220	Job SequencingProblem	GeeksForGeeks	0	0	0	-
221	Huffman Coding	GeeksForGeeks	0	0	0	-
222	Water Connection Problem	GeeksForGeeks	0	0	0	-
223	Fractional Knapsack Problem	GeeksForGeeks	0	0	0	-
224	Greedy Algorithm to find Minimum number of Coins	GeeksForGeeks	0	0	0	-
225	Maximum trains for which stoppage can be provided	GeeksForGeeks	0	0	0	-
226	Minimum Platforms Problem	GeeksForGeeks	0	0	0	-
227	Buy Maximum Stocks if i stocks can be bought on i-th day	GeeksForGeeks	0	0	0	-
228	Find the minimum and maximum amount to buy all N candies	GeeksForGeeks	0	0	0	-
229	Minimize Cash Flow among a given set of friends who have borrowed money from each other	GeeksForGeeks	0	0	0	-
230	Minimum Cost to cut a board into squares	GeeksForGeeks	0	0	0	-
231	Check if it is possible to survive on Island	GeeksForGeeks	0	0	0	-
232	Find maximum meetings in one room	GeeksForGeeks	0	0	0	-
233	Maximum product subset of an array	GeeksForGeeks	0	0	0	-
234	Maximize array sum after K negations	GeeksForGeeks	0	0	0	-
235	Maximize the sum of arr[i] * i	GeeksForGeeks	0	0	0	-
236	Maximum sum of absolute difference of an array	GeeksForGeeks	0	0	0	-
237	Maximize sum of consecutive differences in a circular array	GeeksForGeeks	0	0	0	-
238	Minimum sum of absolute difference of pairs of two arrays	GeeksForGeeks	0	0	0	-
239	Program for Shortest Job First (or SJF) CPU Scheduling	GeeksForGeeks	0	0	0	-
240	Program for Least Recently Used (LRU) Page Replacement algorithm	GeeksForGeeks	0	0	0	-
241	Smallest subset with sum greater than all other elements	GeeksForGeeks	0	0	0	-
242	Chocolate Distribution Problem	GeeksForGeeks	0	0	0	-
243	DEFKIN -Defense of a Kingdom	SPOJ	0	0	0	-
244	DIEHARD -DIE HARD	SPOJ	0	0	0	-
245	GERGOVIA -Wine trading in Gergovia	SPOJ	0	0	0	-
246	Picking Up Chicks	SPOJ	0	0	0	-
247	CHOCOLA –Chocolate	SPOJ	0	0	0	-
248	ARRANGE -Arranging Amplifiers	SPOJ	0	0	0	-
249	K Centers Problem	GeeksForGeeks	0	0	0	-
250	Minimum Cost of ropes	GeeksForGeeks	0	0	0	-
251	Find smallest number with given number of digits and sum of digits	GeeksForGeeks	0	0	0	-
252	Rearrange characters in a string such that no two adjacent are same	GeeksForGeeks	0	0	0	-
253	Find maximum sum possible equal sum of three stacks	GeeksForGeeks	0	0	0	-

BackTracking

S. No.	Problem	Reference	C++	Java	Python	Other languages
254	Rat in a maze Problem	GeeksForGeeks	0	0	0	-
255	Printing all solutions in N-Queen Problem	GeeksForGeeks	0	0	0	-
256	Word Break Problem using Backtracking	GeeksForGeeks	0	0	0	-
257	Remove Invalid Parentheses	LeetCode	0	0	0	-
258	Sudoku Solver	LeetCode	0	0	0	-
259	M Coloring Problem	GeeksForGeeks	0	0	0	-
260	Print all palindromic partitions of a string	GeeksForGeeks	0	0	0	-
261	Subset Sum Problem	GeeksForGeeks	0	0	0	-
262	The Knight’s tour problem	GeeksForGeeks	0	0	0	-
263	Tug of War	GeeksForGeeks	0	0	0	-
264	Find shortest safe route in a path with landmines	GeeksForGeeks	0	0	0	-
265	Combinational Sum	GeeksForGeeks	0	0	0	-
266	Find Maximum number possible by doing at-most K swaps	GeeksForGeeks	0	0	0	-
267	Print all permutations of a string	GeeksForGeeks	0	0	0	-
268	Find if there is a path of more than k length from a source	GeeksForGeeks	0	0	0	-
269	Longest Possible Route in a Matrix with Hurdles	GeeksForGeeks	0	0	0	-
270	Print all possible paths from top left to bottom right of a mXn matrix	GeeksForGeeks	0	0	0	-
271	Partition of a set intoK subsets with equal sum	GeeksForGeeks	0	0	0	-
272	Find the K-th Permutation Sequence of first N natural numbers	GeeksForGeeks	0	0	0	-

Stacks & Queues

S. No.	Problem	Reference	C++	Java	Python	Other languages
273	Implement Stack from Scratch	TutorialsPoint	0	0	0	-
274	Implement Queue from Scratch	GeeksForGeeks	0	0	0	-
275	Implement 2 stack in an array	GeeksForGeeks	0	0	0	-
276	Find the middle element of a stack	GeeksForGeeks	0	0	0	-
277	Implement "N" stacks in an Array	GeeksForGeeks	0	0	0	-
278	Check the expression has valid or Balanced parenthesis or not	GeeksForGeeks	0	0	0	-
279	Reverse a String using Stack	GeeksForGeeks	0	0	0	-
280	Design a Stack that supports getMin() in O(1) time and O(1) extra space	GeeksForGeeks	0	0	0	-
281	Find the next Greater element	GeeksForGeeks	0	0	0	-
282	The celebrity Problem	GeeksForGeeks	0	0	0	-
283	Arithmetic Expression evaluation	GeeksForGeeks.)	0	0	0	-
284	Evaluation of Postfix expression	GeeksForGeeks	0	0	0	-
285	Implement a method to insert an element at its bottom without using any other data structure	StackOverflow	0	0	0	-
286	Reverse a stack using recursion	GeeksForGeeks	0	0	0	-
287	Sort a Stack using recursion	GeeksForGeeks	0	0	0	-
288	Merge Overlapping Intervals	GeeksForGeeks	0	0	0	-
289	Largest rectangular Area in Histogram	GeeksForGeeks	0	0	0	-
290	Length of the Longest Valid Substring	GeeksForGeeks	0	0	0	-
291	Expression contains redundant bracket or not	GeeksForGeeks	0	0	0	-
292	Implement Stack using Queue	GeeksForGeeks	0	0	0	-
293	Implement Stack using Deque	GeeksForGeeks	0	0	0	-
294	[Stack Permutations (Check if an array is stack permutation of other)](https://github.com/draco-malfoy/DCS-LoveBabbar/tree/main/Database/Stacks%20%26%20Queues/Stack%20Permutations%20(Check%20if%20an%20array%20is%20stack%20permutation%20of%20other)	GeeksForGeeks)	0	0	0	-
295	Implement Queue using Stack	GeeksForGeeks	0	0	0	-
296	Implement "n" queue in an array	GeeksForGeeks	0	0	0	-
297	Implement a Circular queue	GeeksForGeeks	0	0	0	-
298	LRU Cache Implementationa	GeeksForGeeks	0	0	0	-
299	Reverse a Queue using recursion	GeeksForGeeks	0	0	0	-
300	Reverse the first “K” elements of a queue	GeeksForGeeks	0	0	0	-
301	Interleave the first half of the queue with second half	GeeksForGeeks	0	0	0	-
302	Find the first circular tour that visits all Petrol Pumps	GeeksForGeeks	0	0	0	-
303	Minimum time required to rot all oranges	GeeksForGeeks	0	0	0	-
304	Distance of nearest cell having 1 in a binary matrix	GeeksForGeeks	0	0	0	-
305	First negative integer in every window of size “k”	GeeksForGeeks	0	0	0	-
306	Check if all levels of two trees are anagrams or not	GeeksForGeeks	0	0	0	-
307	Sum of minimum and maximum elements of all subarrays of size “k”	GeeksForGeeks	0	0	0	-
308	Minimum sum of squares of character counts in a given string after removing “k” characters	GeeksForGeeks	0	0	0	-
309	Queue based approach or first non-repeating character in a stream	GeeksForGeeks	0	0	0	-
310	Next Smaller Element	GeeksForGeeks	0	0	0	-

Heap

S. No.	Problem	Reference	C++	Java	Python	Other languages
311	Implement a Maxheap/MinHeap using arrays and recursion	GeeksForGeeks	0	0	0	-
312	Sort an Array using heap. (HeapSort)	GeeksForGeeks	0	0	0	-
313	Maximum of all subarrays of size k	GeeksForGeeks	0	0	0	-
314	“k” largest element in an array	GeeksForGeeks	0	0	0	-
315	Kth smallest and largest element in an unsorted array	GeeksForGeeks	0	0	0	-
316	Merge “K” sorted arrays. [ IMP ]	GeeksForGeeks	0	0	0	-
317	Merge 2 Binary Max Heaps	GeeksForGeeks	0	0	0	-
318	Kth largest sum continuous subarrays	GeeksForGeeks	0	0	0	-
319	Leetcode- reorganize strings	LeetCode	0	0	0	-
320	Merge “K” Sorted Linked Lists [V.IMP]	GeeksForGeeks	0	0	0	-
321	Smallest range in “K” Lists	GeeksForGeeks	0	0	0	-
322	Median in a stream of Integers	GeeksForGeeks	0	0	0	-
323	Check if a Binary Tree is Heap	GeeksForGeeks	0	0	0	-
324	Connect “n” ropes with minimum cost	GeeksForGeeks	0	0	0	-
325	Convert BST to Min Heap	GeeksForGeeks	0	0	0	-
326	Convert min heap to max heap	GeeksForGeeks	0	0	0	-
327	Rearrange characters in a string such that no two adjacent are same	GeeksForGeeks	0	0	0	-
328	Minimum sum of two numbers formed from digits of an array	GeeksForGeeks	0	0	0	-

Graph

S. No.	Problem	Reference	C++	Java	Python	Other languages
329	Create a Graph, print it	OneDrive	0	0	0	-
330	Implement BFS algorithm	GeeksForGeeks	0	0	0	-
331	Implement DFS Algo	GeeksForGeeks	0	0	0	-
332	Detect Cycle in Directed Graph using BFS/DFS Algo	GeeksForGeeks	0	0	0	-
333	Detect Cycle in UnDirected Graph using BFS/DFS Algo	GeeksForGeeks	0	0	0	-
334	Search in a Maze	GeeksForGeeks	0	0	0	-
335	Minimum Step by Knight	GeeksForGeeks	0	0	0	-
336	Flood fill algo	LeetCode	0	0	0	-
337	Clone a graph	GeeksForGeeks	0	0	0	-
338	Making wired Connections	LeetCode	0	0	0	-
339	Word Ladder	LeetCode	0	0	0	-
340	Dijkstra algo	GeeksForGeeks	0	0	0	-
341	Implement Topological Sort	GeeksForGeeks	0	0	0	-
342	Minimum time taken by each job to be completed given by a Directed Acyclic Graph	GeeksForGeeks	0	0	0	-
343	Find whether it is possible to finish all tasks or not from given dependencies	GeeksForGeeks	0	0	0	-
344	Find the no. of Islands	GeeksForGeeks	0	0	0	-
345	Given a sorted Dictionary of an Alien Language, find order of characters	GeeksForGeeks	0	0	0	-
346	Implement Kruksal’sAlgorithm	GeeksForGeeks	0	0	0	-
347	Implement Prim’s Algorithm	GeeksForGeeks	0	0	0	-
348	Total no. of Spanning tree in a graph	GeeksForGeeks	0	0	0	-
349	Implement Bellman Ford Algorithm	GeeksForGeeks	0	0	0	-
350	Implement Floyd warshall Algorithm	GeeksForGeeks	0	0	0	-
351	Travelling Salesman Problem	GeeksForGeeks	0	0	0	-
352	Graph ColouringProblem	GeeksForGeeks	0	0	0	-
353	Snake and Ladders Problem	GeeksForGeeks	0	0	0	-
354	Find bridge in a graph	GeeksForGeeks	0	0	0	-
355	Count Strongly connected Components(Kosaraju Algo)	GeeksForGeeks	0	0	0	-
356	Check whether a graph is Bipartite or Not	GeeksForGeeks	0	0	0	-
357	Detect Negative cycle in a graph	GeeksForGeeks	0	0	0	-
358	Longest path in a Directed Acyclic Graph	GeeksForGeeks	0	0	0	-
359	Journey to the Moon	HackerRank	0	0	0	-
360	Cheapest Flights Within K Stops	LeetCode	0	0	0	-
361	Oliver and the Game	HackerEarth	0	0	0	-
362	Water Jug problem using BFS	GeeksForGeeks	0	0	0	-
363	Water Jug problem using DFS	GeeksForGeeks	0	0	0	-
364	Find if there is a path of more thank length from a source	GeeksForGeeks	0	0	0	-
365	M-ColouringProblem	GeeksForGeeks	0	0	0	-
366	Minimum edges to reverse o make path from source to destination	GeeksForGeeks	0	0	0	-
367	Paths to travel each nodes using each edge(Seven Bridges)	GeeksForGeeks	0	0	0	-
368	Vertex Cover Problem	GeeksForGeeks	0	0	0	-
369	Chinese Postman or Route Inspection	GeeksForGeeks	0	0	0	-
370	Number of Triangles in a Directed and Undirected Graph	GeeksForGeeks	0	0	0	-
371	Minimise the cashflow among a given set of friends who have borrowed money from each other	GeeksForGeeks	0	0	0	-
372	Two Clique Problem	GeeksForGeeks	0	0	0	-

Trie

S. No.	Problem	Reference	C++	Java	Python	Other languages
373	Construct a trie from scratch	GeeksForGeeks	0	0	0	-
374	Find shortest unique prefix for every word in a given list	GeeksForGeeks	0	0	0	-
375	Word Break Problem - (Trie solution)	GeeksForGeeks	0	0	0	-
376	Given a sequence of words, print all anagrams together	GeeksForGeeks	0	0	0	-
377	Implement a Phone Directory	GeeksForGeeks	0	0	0	-
378	Print unique rows in a given boolean matrix	GeeksForGeeks	0	0	0	-

Dynamic Programming

S. No.	Problem	Reference	C++	Java	Python	Other languages
379	Coin ChangeProblem	GeeksForGeeks	0	0	0	-
380	Knapsack Problem	GeeksForGeeks	0	0	0	-
381	Binomial CoefficientProblem	GeeksForGeeks	0	0	0	-
382	Permutation CoefficientProblem	GeeksForGeeks	0	0	0	-
383	Program for nth Catalan Number	GeeksForGeeks	0	0	0	-
384	Matrix Chain Multiplication	GeeksForGeeks	0	0	0	-
385	Edit Distance	GeeksForGeeks	0	0	0	-
386	Subset Sum Problem	GeeksForGeeks	0	0	0	-
387	Friends Pairing Problem	GeeksForGeeks	0	0	0	-
388	Gold Mine Problem	GeeksForGeeks	0	0	0	-
389	Assembly Line SchedulingProblem	GeeksForGeeks	0	0	0	-
390	Painting the Fence problem	GeeksForGeeks	0	0	0	-
391	Maximize The Cut Segments	GeeksForGeeks	0	0	0	-
392	Longest Common Subsequence	GeeksForGeeks	0	0	0	-
393	Longest Repeated Subsequence	GeeksForGeeks	0	0	0	-
394	Longest Increasing Subsequence	GeeksForGeeks	0	0	0	-
395	Space Optimized Solution of LCS	GeeksForGeeks	0	0	0	-
396	LCS (Longest Common Subsequence) of three strings	GeeksForGeeks	0	0	0	-
397	Maximum Sum Increasing Subsequence	GeeksForGeeks	0	0	0	-
398	Count all subsequences having product less than K	GeeksForGeeks	0	0	0	-
399	Longest subsequence such that difference between adjacent is one	GeeksForGeeks	0	0	0	-
400	Maximum subsequence sum such that no three are consecutive	GeeksForGeeks	0	0	0	-
401	Egg Dropping Problem	GeeksForGeeks	0	0	0	-
402	Maximum Length Chain of Pairs	GeeksForGeeks	0	0	0	-
403	Maximum size square sub-matrix with all 1s	GeeksForGeeks	0	0	0	-
404	Maximum sum of pairs with specific difference	GeeksForGeeks	0	0	0	-
405	Min Cost PathProblem	GeeksForGeeks	0	0	0	-
406	Maximum difference of zeros and ones in binary string	GeeksForGeeks	0	0	0	-
407	Minimum number of jumps to reach end	GeeksForGeeks	0	0	0	-
408	Minimum cost to fill given weight in a bag	GeeksForGeeks	0	0	0	-
409	Minimum removals from array to make max –min <= K	GeeksForGeeks	0	0	0	-
410	Longest Common Substring	GeeksForGeeks	0	0	0	-
411	Count number of ways to reach a given score in a game	GeeksForGeeks	0	0	0	-
412	Count Balanced Binary Trees of Height h	GeeksForGeeks	0	0	0	-
413	LargestSum Contiguous Subarray [V>V>V>V IMP ]	GeeksForGeeks	0	0	0	-
414	Smallest sum contiguous subarray	GeeksForGeeks	0	0	0	-
415	Unbounded Knapsack (Repetition of items allowed)	GeeksForGeeks	0	0	0	-
416	Word Break Problem	GeeksForGeeks	0	0	0	-
417	Largest Independent Set Problem	GeeksForGeeks	0	0	0	-
418	Partition problem	GeeksForGeeks	0	0	0	-
419	Longest Palindromic Subsequence	GeeksForGeeks	0	0	0	-
420	Count All Palindromic Subsequence in a given String	GeeksForGeeks	0	0	0	-
421	Longest Palindromic Substring	LeetCode	0	0	0	-
422	Longest alternating subsequence	GeeksForGeeks	0	0	0	-
423	Weighted Job Scheduling	GeeksForGeeks	0	0	0	-
424	Coin game winner where every player has three choices	GeeksForGeeks	0	0	0	-
425	Count Derangements (Permutation such that no element appears in its original position) [ IMPORTANT ]	GeeksForGeeks	0	0	0	-
426	Maximum profit by buying and selling a share at most twice [ IMP ]	GeeksForGeeks	0	0	0	-
427	Optimal Strategy for a Game	GeeksForGeeks	0	0	0	-
428	Optimal Binary Search Tree	GeeksForGeeks	0	0	0	-
429	Palindrome PartitioningProblem	GeeksForGeeks	0	0	0	-
430	Word Wrap Problem	GeeksForGeeks	0	0	0	-
431	Mobile Numeric Keypad Problem [ IMP ]	GeeksForGeeks	0	0	0	-
432	Boolean Parenthesization Problem	GeeksForGeeks	0	0	0	-
433	Largest rectangular sub-matrix whose sum is 0	GeeksForGeeks	0	0	0	-
434	Largest area rectangular sub-matrix with equal number of 1’s and 0’s [ IMP ]	GeeksForGeeks	0	0	0	-
435	Maximum sum rectangle in a 2D matrix	GeeksForGeeks	0	0	0	-
436	Maximum profit by buying and selling a share at most k times	GeeksForGeeks	0	0	0	-
437	Find if a string is interleaved of two other strings	GeeksForGeeks	0	0	0	-
438	Maximum Length of Pair Chain	LeetCode	0	0	0	-

Bit Manipulation

S. No.	Problem	Reference	C++	Java	Python	Other languages
439	Count set bits in an integer	GeeksForGeeks	0	0	0	-
440	Find the two non-repeating elements in an array of repeating elements	GeeksForGeeks	0	0	0	-
441	Count number of bits to be flipped to convert A to B	GeeksForGeeks	0	0	0	-
442	Count total set bits in all numbers from 1 to n	GeeksForGeeks	0	0	0	-
443	Program to find whether a no is power of two	GeeksForGeeks	0	0	0	-
444	Find position of the only set bit	GeeksForGeeks	0	0	0	-
445	Copy set bits in a range	GeeksForGeeks	0	0	0	-
446	Divide two integers without using multiplication, division and mod operator	GeeksForGeeks	0	0	0	-
447	Calculate square of a number without using * or / or pow()	GeeksForGeeks	0	0	0	-
448	Power Set	GeeksForGeeks	0	0	0	-

Contributors

Contributing Guidelines

Please look here.