Leetcode 30 Day Challenge [April 1,2020 - April 30,2020]

Leetcode is currently running a 30 day challenge to make use of lock down in useful way. So for the month of April , each day they release a new problem till April 30, 2020. Here are the list of questions and solutions with explanation till date. Solve each problem within 24 hours from it's opening time to receive coins reward.

DAY 1 - Single Number

DAY 2 - Happy Number

DAY 3 - Maximum Subarray

DAY 4 - Move Zeroes

DAY 5 - Best Time to Buy and Sell Stock II

DAY 6 - Group Anagrams

DAY 7 - Counting Elements

DAY 8 - Middle of the Linked List

DAY 9 - Backspace String Compare

DAY 10 - Min Stack

DAY 11 - Diameter of Binary Tree

DAY 12 - Last Stone Weight 

DAY 13 - Contiguous Array

DAY 14 - Perform String Shifts

DAY 15 - Product of Array Except Self 

DAY 16 - Valid Parenthesis String

DAY 17 - Number of Islands

DAY 18 - Minimum Path Sum

DAY 19 - Search in Rotated Sorted Array 

DAY 20 - Construct Binary Search Tree from Preorder traversal

DAY 21 - Leftmost column with atleast a one

DAY 22 - Subarray Sum equals K

DAY 23 - Bitwise AND of Numbers Range 

DAY 24 - LRU Cache

DAY 25 - Jump Game  

DAY 26 - Longest Common Subsequence

DAY 27 - Maximal Square

DAY 28 - First Unique Number

DAY 29 - Binary Tree Maximum Path Sum

DAY 30 - Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree


It is happy to share here on because of successful completion of April 30 day challenge, Leetcode is again going to conduct May 31 day challenge.

Check out here for Leetcode 31 day challenge[May 1.2020 - May 31,2020]

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Happy Coding..!!😍

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