Leetcode Solutions

Introduction

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Leetcode Questions

• LeetCode 1. Two Sum

• LeetCode 2. Add Two Numbers

• LeetCode 3. Longest Substring Without Repeating Characters

• LeetCode 4. Median of Two Sorted Arrays

• LeetCode 5. Longest Palindromic Substring

• LeetCode 6. ZigZag Conversion

• LeetCode 7. Reverse Integer

• LeetCode 8. String to Integer (atoi)

• LeetCode 9. Palindrome Number

• LeetCode 10. Regular Expression Matching

• LeetCode 11. Container With Most Water

• LeetCode 12. Integer to Roman

• LeetCode 13. Roman to Integer

• LeetCode 14. Longest Common Prefix

• LeetCode 15. 3Sum

• LeetCode 16. 3Sum Closest

• LeetCode 17. Letter Combinations of a Phone Number

• LeetCode 18. 4Sum

• LeetCode 19. Remove Nth Node From End of List

• LeetCode 20. Valid Parentheses

• LeetCode 21. Merge Two Sorted Lists

• LeetCode 22. Generate Parentheses

• LeetCode 23. Merge k Sorted Lists

• LeetCode 24. Swap Nodes in Pairs

• LeetCode 25. Reverse Nodes in k-Group

• LeetCode 26. Remove Duplicates from Sorted Array

• LeetCode 27. Remove Element

• LeetCode 28. Implement strStr()

• LeetCode 29. Divide Two Integers

• LeetCode 30. Substring with Concatenation of All Words

• LeetCode 31. Next Permutation

• LeetCode 32. Longest Valid Parentheses

• LeetCode 33. Search in Rotated Sorted Array

• LeetCode 42. Trapping Rain Water

• LeetCode 56. Merge Intervals

• LeetCode 67. Add Binary

• LeetCode 81. Search in Rotated Sorted Array II

• LeetCode 124. Binary Tree Maximum Path Sum

• LeetCode 125. Valid Palindrome

• LeetCode 153. Find Minimum in Rotated Sorted Array

• LeetCode 154. Find Minimum in Rotated Sorted Array II

• LeetCode 157. Read N Characters Given Read4

• LeetCode 158. Read N Characters Given Read4 II - Call multiple times

• LeetCode 236. Lowest Common Ancestor of a Binary Tree

• LeetCode 238. Product of Array Except Self

• LeetCode 269. Alien Dictionary

• LeetCode 295. Find Median from Data Stream

• LeetCode 297. Serialize and Deserialize Binary Tree

• LeetCode 300. Longest Increasing Subsequence

• LeetCode 301. Remove Invalid Parentheses

• LeetCode 336. Palindrome Pairs

• LeetCode 407. Trapping Rain Water II

• LeetCode 415. Add Strings

• LeetCode 426. Convert Binary Search Tree to Sorted Doubly Linked List

• LeetCode 489. Robot Room Cleaner

• LeetCode 560. Subarray Sum Equals K

• LeetCode 680. Valid Palindrome II

• LeetCode 710. Random Pick with Blacklist

• LeetCode 721. Accounts Merge

• LeetCode 863. All Nodes Distance K in Binary Tree

• LeetCode 918. Maximum Sum Circular Subarray

• LeetCode 953. Verifying an Alien Dictionary

• LeetCode 973. K Closest Points to Origin

• LeetCode 1249. Minimum Remove to Make Valid Parentheses

• LeetCode 1428. Leftmost Column with at Least a One

• LeetCode 1570. Dot Product of Two Sparse Vectors

• LeetCode 1644. Lowest Common Ancestor of a Binary Tree II

• LeetCode 1650. Lowest Common Ancestor of a Binary Tree III

• LeetCode 1676. Lowest Common Ancestor of a Binary Tree IV

• LeetCode 1727. Largest Submatrix With Rearrangements

• LeetCode 1751. Maximum Number of Events That Can Be Attended II

• LeetCode 1754. Largest Merge Of Two Strings

• LeetCode 1755. Closest Subsequence Sum

• LeetCode 1760. Minimum Limit of Balls in a Bag

• LeetCode 1761. Minimum Degree of a Connected Trio in a Graph

• LeetCode 1764. Form Array by Concatenating Subarrays of Another Array

• LeetCode 1765. Map of Highest Peak

• LeetCode 1766. Tree of Coprimes

• LeetCode 1770. Maximum Score from Performing Multiplication Operations

• LeetCode 1771. Maximize Palindrome Length From Subsequences

• LeetCode 1774. Closest Dessert Cost

• LeetCode 1775. Equal Sum Arrays With Minimum Number of Operations

• LeetCode 1776. Car Fleet II

• LeetCode 1778. Shortest Path in a Hidden Grid

• LeetCode 1779. Find Nearest Point That Has the Same X or Y Coordinate

• LeetCode 1780. Check if Number is a Sum of Powers of Three

• LeetCode 1781. Sum of Beauty of All Substrings

• LeetCode 1782. Count Pairs Of Nodes

• LeetCode 1784. Check if Binary String Has at Most One Segment of Ones

• LeetCode 1785. Minimum Elements to Add to Form a Given Sum

• LeetCode 1786. Number of Restricted Paths From First to Last Node

• LeetCode 1787. Make the XOR of All Segments Equal to Zero

• LeetCode 1788. Maximize the Beauty of the Garden

• LeetCode 1790. Check if One String Swap Can Make Strings Equal

• LeetCode 1791. Find Center of Star Graph

• LeetCode 1792. Maximum Average Pass Ratio

• LeetCode 1793. Maximum Score of a Good Subarray

• LeetCode 1794. Count Pairs of Equal Substrings With Minimum Difference

• LeetCode 1796. Second Largest Digit in a String

• LeetCode 1797. Design Authentication Manager

• LeetCode 1798. Maximum Number of Consecutive Values You Can Make

• LeetCode 1799. Maximize Score After N Operations

• LeetCode 1800. Maximum Ascending Subarray Sum

• LeetCode 1801. Number of Orders in the Backlog

• LeetCode 1802. Maximum Value at a Given Index in a Bounded Array

• LeetCode 1803. Count Pairs With XOR in a Range

• LeetCode 1804. Implement Trie II (Prefix Tree)

• LeetCode 1805. Number of Different Integers in a String

• LeetCode 1807. Evaluate the Bracket Pairs of a String

• LeetCode 1808. Maximize Number of Nice Divisors

• LeetCode 1810. Minimum Path Cost in a Hidden Grid

• LeetCode 1812. Determine Color of a Chessboard Square

• LeetCode 1813. Sentence Similarity III

• LeetCode 1814. Count Nice Pairs in an Array

• LeetCode 1815. Maximum Number of Groups Getting Fresh Donuts

• LeetCode 1816. Truncate Sentence

• LeetCode 1817. Finding the Users Active Minutes

• LeetCode 1818. Minimum Absolute Sum Difference

• LeetCode 1819. Number of Different Subsequences GCDs

• LeetCode 1820. Maximum Number of Accepted Invitations

• LeetCode 1822. Sign of the Product of an Array

• LeetCode 1824. Minimum Sideway Jumps

• LeetCode 1825. Finding MK Average

• LeetCode 1826. Faulty Sensor

• LeetCode 1827. Minimum Operations to Make the Array Increasing

• LeetCode 1828. Queries on Number of Points Inside a Circle

• LeetCode 1829. Maximum XOR for Each Query

• LeetCode 1830. Minimum Number of Operations to Make String Sorted

• LeetCode 1832. Check if the Sentence Is Pangram

• LeetCode 1833. Maximum Ice Cream Bars

• LeetCode 1834. Single-Threaded CPU

• LeetCode 1835. Find XOR Sum of All Pairs Bitwise AND

• LeetCode 1836. Remove Duplicates From an Unsorted Linked List

• LeetCode 1837. Sum of Digits in Base K

• LeetCode 1839. Longest Substring Of All Vowels in Order

• LeetCode 1840. Maximum Building Height

• LeetCode 1847. Closest Room

• LeetCode 1850. Minimum Adjacent Swaps to Reach the Kth Smallest Number

• LeetCode 1851. Minimum Interval to Include Each Query

Leetcode 297. Serialize and Deserialize Binary Tree