fraz-leetcode-hot-250

250 must solve leetcode questions spanning across various dsa topics.

Table Of Contents

Sl. No.	Problem Name/Link	Difficulty	Solution Link
Array
1	Two Sum	🍏	👉
2	Best Time To Buy and Sell Stock	🍏	👉
3	Merge Sorted Array	🍏	👉
4	Move Zeroes	🍏	👉
5	Best Time To Buy and Sell Stock II	🍋	👉
6	Running Sum of 1d Array	🍏	👉
7	Find Pivot Index	🍋	👉
8	Majority Element	🍏	👉
9	Fibonacci Number	🍏	👉
10	Squares of a Sorted Array	🍏	👉
11	Pascal's Triangle	🍏	👉
12	Remove Duplicates from Sorted Array	🍋	👉
13	3 Sum	🍋	👉
14	Product of Array Except Self	🍋	👉
15	Insert Delete GetRandom O(1)	🍋	👉
16	Subarray Sum Equals K	🍋	👉
17	Next Permutation	🍋	👉
18	Spiral Matrix	🍋	👉
19	Container With Most Water	🍋	👉
20	Rotate Image	🍋	👉
21	Word Search	🍋	👉
22	3Sum Closest	🍋	👉
23	Game of Life	🍋	👉
24	Pairs of Songs With Total Durations Divisible by 60	🍋	👉
25	4 Sum	🍋	👉
26	Find the Duplicate Number	🍋	👉
27	Combination Sum	🍋	👉
28	Jump Game II	🍋	👉
29	Maximum Points You Can Obtain from Cards	🍋	👉
30	Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts	🍋	👉
31	Max Area of Island	🍋	👉
32	Find All Duplicates in an Array	🍋	👉
33	K-diff Pairs in an Array	🍋	👉
34	Subsets	🍋	👉
35	Invalid Transactions	🍋	👉
36	Jump Game I	🍋	👉
37	Subarray Sums Divisible by K	🍋	👉
38	First Missing Positive	🍎	👉
39	Largest Rectangle in Histogram	🍎	👉
40	Insert Delete GetRandom O(1) - Duplicates allowed	🍎	👉
41	Best Time to Buy and Sell Stock III	🍎	👉
42	Max Value of Equation	🍎	👉
Recursion
1	Pow(x, n)	🍋	👉
2	Valid Palindrome	🍏	👉
3	Subsets	🍋	👉
4	Permutations	🍋	👉
5	Permutations II	🍋	👉
6	Subsets II	🍋	👉
7	Combinations	🍋	👉
8	Combination Sum	🍋	👉
9	Combination Sum II	🍋	👉
10	Combination Sum III	🍋	👉
11	Letter Combinations of a Phone Number	🍋	👉
12	Partition to K Equal Sum Subsets	🍋	👉
13	Max Length of a Concatenated String with Unique Characters	🍋	👉
14	Flood Fill	🍏	👉
15	Word Search	🍋	👉
16	Rat in a Maze	🍋	👉
17	N Queens	🍎	👉
Dynamic Programming
1	Maximum Subarray	🍋	👉
2	Climbing Stairs	🍏	👉
3	Divisor Game	🍏	👉
4	Counting Bits	🍏	👉
5	Decode Ways	🍋	👉
6	Word Break	🍋	👉
7	Delete and Earn	🍋	👉
8	Maximal Square	🍋	👉
9	Coin Change	🍋	👉
10	Maximum Product Subarray	🍋	👉
11	Maximum Length Of Repeated Subarray	🍋	👉
12	Palindromic Substrings	🍋	👉
13	House Robber	🍋	👉
14	Continuous Subarray Sum	🍋	👉
15	Knight Dialer	🍋	👉
16	Longest Increasing Subsequence	🍋	👉
17	Unique Paths	🍋	👉
18	Count Square Submatrices with All Ones	🍋	👉
19	Range Sum Query 2D Immutable	🍋	👉
20	Longest Arithmetic Subsequence	🍋	👉
21	Trapping Rain Water	🍎	👉
22	Word Break II	🍎	👉
23	Regular Expression Matching	🍎	👉
24	Maximal Rectangle	🍎	👉
25	Longest Valid Parentheses	🍎	👉
26	Edit Distance	🍎	👉
27	Minimum Difficulty Of A Job Schedule	🍎	👉
28	Frog Jump	🍎	👉
29	Best Time To Buy And Sell Stock IV	🍎	👉
30	Burst Balloons	🍎	👉
31	Minimum Cost To Merge Stones	🍎	👉
32	Minimum Insertion Steps To Make A String Palindrome	🍎	👉
33	Super Egg Drop	🍎	👉
34	Count Different Palindromic Subsequences	🍎	👉
35	Minimum Cost To Cut A Stick	🍎	👉
Strings
1	Add Strings	🍏	👉
2	Longest Common Prefix	🍏	👉
3	Valid Palindrome II	🍏	👉
4	Roman To Integer	🍏	👉
5	Find the Index of the First Occurrence in a String	🍏	👉
6	Longest Substring Without Repeating Characters	🍋	👉
7	Minimum Remove To Make Valid Parentheses	🍋	👉
8	Longest Palindromic Substring	🍋	👉
9	Group Anagrams	🍋	👉
10	Generate Parentheses	🍋	👉
11	Basic Calculator 2	🍋	👉
12	Integer to Roman	🍋	👉
13	Reverse Words In A String	🍋	👉
14	Simplify Path	🍋	👉
15	ZigZag Conversion	🍋	👉
16	Text Justification	🍎	👉
17	Integer To English Words	🍎	👉
18	Minimum Window Substring	🍎	👉
19	Valid Number	🍎	👉
20	Valid Number	🍎	👉
21	Smallest Range Covering Elements from K Lists	🍎	👉
22	Substring With Concatenation Of All Words	🍎	👉
Maths
1	Reverse Integer	🍋	👉
2	Add Binary	🍏	👉
3	Add Binary	🍏	👉
4	Palindrome Number	🍏	👉
5	Minimum Moves to Equal Array Elements	🍋	👉
6	Happy Number	🍏	👉
7	Excel Sheet Column Title	🍏	👉
8	Missing Number	🍏	👉
9	Maximum Product of Three Numbers	🍏	👉
10	Power of Two	🍏	👉
11	Encode And Decode TinyURL	🍋	👉
12	String to Integer (atoi)	🍋	👉
13	Multiply Strings	🍋	👉
14	Angle Between Hands of a Clock	🍋	👉
15	Integer Break	🍋	👉
16	Valid Square	🍋	👉
17	The kth Factor of n	🍋	👉
18	Basic Calculator	🍎	👉
19	Max Ponts On A Line	🍎	👉
20	Permutation Sequence	🍎	👉
21	Number of Digit One	🍎	👉
Greedy
1	Task Scheduler	🍋	👉
2	Gas Station	🍋	👉
3	Min Time To Make Rope Colorful	🍋	👉
4	Maximum Number of Events That Can Be Attended	🍋	👉
5	Minimum Deletions to Make Character Frequencies Unique	🍋	👉
6	Remove k digits	🍋	👉
7	Restore the Array From Adjacent Pairs	🍋	👉
8	Non Overlapping Intervals	🍋	👉
9	Candy	🍎	👉
10	Minimum Number of Taps to Open to Water a Garden	🍎	👉
11	Create Maximum Number	🍎	👉
Dfs
1	Letter Combinations of a Phone Number	🍋	👉
2	Course Schedule II	🍋	👉
3	Decode String	🍋	👉
4	Number of Provinces	🍋	👉
5	Clone Graph	🍋	👉
6	Shortest Bridge	🍋	👉
7	All Paths From Source to Target	🍋	👉
8	Surrounded Regions	🍋	👉
9	House Robber III	🍋	👉
10	Critical Connections in a Network	🍎	👉
11	Remove Invalid Parentheses	🍎	👉
12	Longest Increasing Path in a Matrix	🍎	👉
13	Concatenated Words	🍎	👉
14	Making A Large Island	🍎	👉
15	Contain Virus	🍎	👉
16	24 Game	🍎	👉
17	Remove Boxes	🍎	👉
Tree
1	Diameter of Binary Tree	🍏	👉
2	Invert Binary Tree	🍏	👉
3	Subtree of Another Tree	🍏	👉
4	Range Sum of BST	🍏	👉
5	Symmetric Tree	🍏	👉
6	Convert Sorted Array to Binary Search Tree	🍏	👉
7	Merge Two Binary Trees	🍏	👉
8	Maximum Depth of Binary Tree	🍏	👉
9	Binary Tree Paths	🍏	👉
10	Same Tree	🍏	👉
11	Lowest Common Ancestor of a Binary Search Tree	🍏	👉
12	Path Sum	🍏	👉
13	Minimum Absolute Difference in BST	🍏	👉
14	Sum of Left Leaves	🍏	👉
15	Balanced Binary Tree	🍏	👉
16	Binary Tree Inorder Traversal	🍏	👉
17	Count Good Nodes in Binary Tree	🍋	👉
18	Lowest Common Ancestor of a Binary Tree	🍋	👉
19	Binary Tree Right Side View	🍋	👉
19	All Nodes Distance K in Binary Tree	🍋	👉
20	Validate Binary Search Tree	🍋	👉
21	Binary Tree Zigzag Level Order Traversal	🍋	👉
22	Binary Search Tree Iterator	🍋	👉
23	Binary Tree Level Order Traversal	🍋	👉
24	Path Sum III	🍋	👉
25	Construct Binary Tree from Preorder and Postorder Traversal	🍋	👉
26	Unique Binary Search Trees	🍋	👉
27	Recover Binary Search Tree	🍋	👉
28	Populating Next Right Pointers in Each Node	🍋	👉
29	Flatten Binary Tree to Linked List	🍋	👉
30	Maximum Width of Binary Tree	🍋	👉
31	Unique Binary Search Trees II	🍋	👉
32	Kth Smallest Element in a BST	🍋	👉
33	Redundant Connection	🍋	👉
34	Serialize and Deserialize Binary Tree	🍎	👉
35	Binary Tree Maximum Path Sum	🍎	👉
36	Vertical Order Traversal of a Binary Tree	🍎	👉
37	Binary Tree Cameras	🍎	👉
38	Sum of Distances in Tree	🍎	👉
40	Number Of Ways To Reconstruct A Tree	🍎	👉
41	Redundant Connection II	🍎	👉
Hash Table
1	Verifying an Alien Dictionary	🍏	👉
2	Design HashMap	🍏	👉
3	Top K Frequent Elements	🍋	👉
4	Design Twitter	🍋	👉
Binary Search
1	Sqrt(x)	🍏	👉
2	Binary Search	🍏	👉
3	Count Negative Numbers in a Sorted Matrix	🍏	👉
4	Peak Index in a Mountain Array	🍏	👉
5	Time Based Key-Value Store	🍋	👉
6	Search in Rotated Sorted Array	🍋	👉
7	Pow(x, n)	🍋	👉
8	Find First and Last Position of Element in Sorted Array	🍋	👉
9	Find Peak Element	🍋	👉
10	Search a 2D Matrix	🍋	👉
11	Divide Two Integers	🍋	👉
12	Capacity To Ship Packages Within D Days	🍋	👉
13	Minimum Limit of Balls in a Bag	🍋	👉
14	Median of Two Sorted Arrays	🍎	👉
15	Count of Smaller Numbers After Self	🍎	👉
16	Max Sum of Rectangle No Larger Than K	🍎	👉
17	Split Array Largest Sum	🍎	👉
18	Shortest Subarray with Sum at Least K	🍎	👉
BFS
1	Number of Islands	🍋	👉
2	Rotting Oranges	🍋	👉
3	Snakes and Ladders	🍋	👉
4	Is Graph Bipartite?	🍋	👉
5	Minimum Jumps to Reach Home	🍋	👉
6	Word Ladder	🍎	👉
7	Word Ladder II	🍎	👉
8	Cut Off Trees for Golf Event	🍎	👉
9	Reachable Nodes In Subdivided Graph	🍎	👉
Two Pointers
1	Partition Labels	🍋	👉
2	Sort Colors	🍋	👉
3	Longest Repeating Character Replacement	🍋	👉
4	Maximum Number of Visible Points	🍎	👉
5	Subarrays with K Different Integers	🍎	👉
Backtracking
1	Palindrome Partitioning	🍋	👉
2	Combination Sum II	🍋	👉
3	Combinations	🍋	👉
4	Permutations II	🍋	👉
5	Subsets II	🍋	👉
6	Beautiful Arrangement	🍋	👉
7	Word Search II	🍎	👉
8	Sudoku Solver	🍎	👉
9	N-Queens	🍎	👉
10	Unique Paths III	🍎	👉
Stack
1	Min Stack	🍋	👉
2	Next Greater Element I	🍏	👉
3	Backspace String Compare	🍏	👉
4	Implement Queue using Stacks	🍏	👉
5	Binary Tree Preorder Traversal	🍏	👉
6	Binary Tree Postorder Traversal	🍏	👉
7	Binary Tree Inorder Traversal	🍏	👉
8	Implement Stack using Queues	🍏	👉
9	Remove All Adjacent Duplicates in String II	🍋	👉