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January LeetCoding Challenge 2021 Series' Articles
Back to Ruairí O'Brien's Series
Day1 - Check Array Formation Through Concatenation
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Jan 3 '21
Day1 - Check Array Formation Through Concatenation
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2 min read
Week 1 Bonus - Palindrome Permutation
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Jan 3 '21
Week 1 Bonus - Palindrome Permutation
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Day 2 Find a Corresponding Node of a Binary Tree in a Clone of That Tree
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Jan 4 '21
Day 2 Find a Corresponding Node of a Binary Tree in a Clone of That Tree
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Day 3 - Beautiful Arrangement
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Jan 4 '21
Day 3 - Beautiful Arrangement
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Day 4 - Merge Two Sorted Lists
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Jan 4 '21
Day 4 - Merge Two Sorted Lists
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Day 5 - Remove Duplicates from Sorted List II
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Jan 5 '21
Day 5 - Remove Duplicates from Sorted List II
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3 min read
Day 6 - Kth Missing Positive Number
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Jan 6 '21
Day 6 - Kth Missing Positive Number
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Day 7 - Longest Substring Without Repeating Characters
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Jan 7 '21
Day 7 - Longest Substring Without Repeating Characters
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Day 8 - Check If Two String Arrays are Equivalent
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Jan 8 '21
Day 8 - Check If Two String Arrays are Equivalent
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Day 9 - Word Ladder
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Jan 9 '21
Day 9 - Word Ladder
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5 min read
Day 10 - Create Sorted Array through Instructions
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Jan 10 '21
Day 10 - Create Sorted Array through Instructions
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4 min read
Day 11 - Merge Sorted Array
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Jan 11 '21
Day 11 - Merge Sorted Array
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Day 12 - Add Two Numbers
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Jan 12 '21
Day 12 - Add Two Numbers
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Day 13 - Boats to Save People
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Jan 13 '21
Day 13 - Boats to Save People
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Day 14 - Minimum Operations to Reduce X to Zero
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Jan 14 '21
Day 14 - Minimum Operations to Reduce X to Zero
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Week 2 Bonus - Find Root of N-Ary Tree
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Jan 14 '21
Week 2 Bonus - Find Root of N-Ary Tree
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3 min read
Day 15 - Get Maximum in Generated Array
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Jan 15 '21
Day 15 - Get Maximum in Generated Array
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Day 16 - Kth Largest Element in an Array
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Jan 16 '21
Day 16 - Kth Largest Element in an Array
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Day 17 - Count Sorted Vowel Strings
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Jan 17 '21
Day 17 - Count Sorted Vowel Strings
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Day 18 - Max Number of K-Sum Pairs
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Jan 18 '21
Day 18 - Max Number of K-Sum Pairs
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Week 3 Bonus - Nested List Weight Sum
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Jan 19 '21
Week 3 Bonus - Nested List Weight Sum
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Day 19 - Longest Palindromic Substring
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Jan 20 '21
Day 19 - Longest Palindromic Substring
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3 min read
Day 20 - Valid Parentheses
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Jan 20 '21
Day 20 - Valid Parentheses
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Day 21 - Find the Most Competitive Subsequence
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Jan 21 '21
Day 21 - Find the Most Competitive Subsequence
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Day 22 - Determine if Two Strings Are Close
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Jan 22 '21
Day 22 - Determine if Two Strings Are Close
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Day 23 - Sort the Matrix Diagonally
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Jan 23 '21
Day 23 - Sort the Matrix Diagonally
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Day 24 - Merge k Sorted Lists
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Jan 24 '21
Day 24 - Merge k Sorted Lists
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3 min read
Day 25 - Check If All 1's Are at Least Length K Places Away
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Jan 25 '21
Day 25 - Check If All 1's Are at Least Length K Places Away
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Day 28 - Smallest String With A Given Numeric Value
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Jan 28 '21
Day 28 - Smallest String With A Given Numeric Value
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Day 27 - Concatenation of Consecutive Binary Numbers
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Jan 28 '21
Day 27 - Concatenation of Consecutive Binary Numbers
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Day 29 - Vertical Order Traversal of a Binary Tree
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Jan 31 '21
Day 29 - Vertical Order Traversal of a Binary Tree
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Day 30 - Minimize Deviation in Array
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Jan 31 '21
Day 30 - Minimize Deviation in Array
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Day 31 - Next Permutation
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Jan 31 '21
Day 31 - Next Permutation
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1 min read
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