GitHub - LeetCode-in-Elixir/LeetCode-in-Elixir.github.io: Elixir-based LeetCode algorithm problem solutions, regularly updated.

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Level 2

Day 1 Implementation/Simulation

Day 2 String

Day 3 Linked List


0019	Remove Nth Node From End of List	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Big_O_Time_O(L)_Space_O(L)	275	100.00
0234	Palindrome Linked List	Easy	Top_100_Liked_Questions, Two_Pointers, Stack, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1)	583	100.00

Day 4 Linked List


0148	Sort List	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(log(N))_Space_O(log(N))	489	100.00

Day 5 Greedy

Day 6 Tree


0226	Invert Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n)	233	100.00

Day 7 Tree


0543	Diameter of Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n)	264	100.00
0437	Path Sum III	Medium	Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n)	336	100.00

Day 8 Binary Search


0074	Search a 2D Matrix	Medium	Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1)	253	100.00
0033	Search in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	292	100.00

Day 9 Binary Search Tree


0230	Kth Smallest Element in a BST	Medium	Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n)	286	66.67

Day 10 Graph/BFS/DFS

Day 11 Graph/BFS/DFS

Day 12 Dynamic Programming


0198	House Robber	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	249	100.00
0322	Coin Change	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount)	1402	100.00

Day 13 Dynamic Programming


0416	Partition Equal Subset Sum	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Big_O_Time_O(nsums)_Space_O(nsums)	1982	100.00
0152	Maximum Product Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	322	100.00

Day 14 Sliding Window/Two Pointer


0003	Longest Substring Without Repeating Characters	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1)	356	93.33

Day 15 Tree


0101	Symmetric Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N))	255	60.00

Day 16 Design


0155	Min Stack	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N)	385	100.00
0208	Implement Trie (Prefix Tree)	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N)	724	100.00

Day 17 Interval


0056	Merge Intervals	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n)	305	100.00

Day 18 Stack

Day 19 Union Find

Day 20 Brute Force/Backtracking


0039	Combination Sum	Medium	Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n)	264	100.00
0046	Permutations	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!)	225	100.00

Udemy

Udemy Integers


0136	Single Number	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1)	295	100.00
0007	Reverse Integer	Medium	Top_Interview_Questions, Math	317	100.00
0009	Palindrome Number	Easy	Math	1007	87.50

Udemy Strings


0003	Longest Substring Without Repeating Characters	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1)	356	93.33
0020	Valid Parentheses	Easy	Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n)	252	81.48
0005	Longest Palindromic Substring	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	337	100.00
0394	Decode String	Medium	Top_100_Liked_Questions, String, Stack, Recursion, Big_O_Time_O(n)_Space_O(n)	268	100.00
0049	Group Anagrams	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n)	339	66.67

Udemy Binary Search


0033	Search in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	292	100.00
0153	Find Minimum in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N)	991	100.00

Udemy Arrays


0121	Best Time to Buy and Sell Stock	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	797	30.00
0001	Two Sum	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n)	261	94.89
0055	Jump Game	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1)	437	100.00
0238	Product of Array Except Self	Medium	Top_100_Liked_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n)	362	85.71
0041	First Missing Positive	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n)	806	100.00
0239	Sliding Window Maximum	Hard	Top_100_Liked_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Big_O_Time_O(n*k)_Space_O(n+k)	1405	100.00

Udemy Two Pointers


0042	Trapping Rain Water	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1)	280	100.00
0015	3Sum	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2)	717	100.00

Udemy Famous Algorithm


0053	Maximum Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1)	920	100.00
0169	Majority Element	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1)	278	100.00

Udemy Sorting Algorithms

Udemy 2D Arrays/Matrix


0074	Search a 2D Matrix	Medium	Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1)	253	100.00
0056	Merge Intervals	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n)	305	100.00

Udemy Linked List


0024	Swap Nodes in Pairs	Medium	Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1)	244	66.67
0206	Reverse Linked List	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1)	278	100.00
0021	Merge Two Sorted Lists	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n)	261	85.00
0234	Palindrome Linked List	Easy	Top_100_Liked_Questions, Two_Pointers, Stack, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1)	583	100.00
0025	Reverse Nodes in k-Group	Hard	Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k)	237	100.00

Udemy Tree Stack Queue


0094	Binary Tree Inorder Traversal	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n)	225	100.00
0102	Binary Tree Level Order Traversal	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N)	252	100.00
0543	Diameter of Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n)	264	100.00
0226	Invert Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n)	233	100.00
0104	Maximum Depth of Binary Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H)	254	100.00
0124	Binary Tree Maximum Path Sum	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N)	291	100.00
0098	Validate Binary Search Tree	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N))	239	100.00

Udemy Trie and Heap


0208	Implement Trie (Prefix Tree)	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N)	724	100.00

Udemy Graph


0200	Number of Islands	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(MN)_Space_O(MN)	463	100.00

Udemy Dynamic Programming


0139	Word Break	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max)	263	100.00
0152	Maximum Product Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	322	100.00
0198	House Robber	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	249	100.00
0070	Climbing Stairs	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n)	255	100.00
0064	Minimum Path Sum	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(mn)_Space_O(mn)	285	100.00
0300	Longest Increasing Subsequence	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n)	259	100.00
1143	Longest Common Subsequence	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(nm)_Space_O(nm)	722	100.00
0072	Edit Distance	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2)	675	100.00
0010	Regular Expression Matching	Hard	Top_Interview_Questions, String, Dynamic_Programming, Recursion, Big_O_Time_O(mn)_Space_O(mn)	296	100.00

Udemy Backtracking/Recursion


0022	Generate Parentheses	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(2^n)_Space_O(n)	229	100.00
0039	Combination Sum	Medium	Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n)	264	100.00
0078	Subsets	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Big_O_Time_O(2^n)_Space_O(n*2^n)	229	100.00
0017	Letter Combinations of a Phone Number	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Big_O_Time_O(4^n)_Space_O(n)	279	100.00
0046	Permutations	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!)	225	100.00

Udemy Bit Manipulation


0338	Counting Bits	Easy	Dynamic_Programming, Bit_Manipulation, Big_O_Time_O(num)_Space_O(num)	330	100.00

Udemy Design


0155	Min Stack	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N)	385	100.00

Data Structure I

Day 1 Array


0053	Maximum Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1)	920	100.00

Day 2 Array


0001	Two Sum	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n)	261	94.89

Day 3 Array


0121	Best Time to Buy and Sell Stock	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	797	30.00

Day 4 Array

Day 5 Array


0074	Search a 2D Matrix	Medium	Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1)	253	100.00

Day 6 String

Day 7 Linked List


0021	Merge Two Sorted Lists	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n)	261	85.00

Day 8 Linked List


0206	Reverse Linked List	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1)	278	100.00

Day 9 Stack Queue


0020	Valid Parentheses	Easy	Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n)	252	81.48

Day 10 Tree


0094	Binary Tree Inorder Traversal	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n)	225	100.00

Day 11 Tree


0102	Binary Tree Level Order Traversal	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N)	252	100.00
0104	Maximum Depth of Binary Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H)	254	100.00
0101	Symmetric Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N))	255	60.00

Day 12 Tree


0226	Invert Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n)	233	100.00

Day 13 Tree

Day 14 Tree


0098	Validate Binary Search Tree	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N))	239	100.00

Data Structure II

Day 1 Array


0136	Single Number	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1)	295	100.00
0169	Majority Element	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1)	278	100.00
0015	3Sum	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2)	717	100.00

Day 2 Array


0056	Merge Intervals	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n)	305	100.00

Day 3 Array

Day 4 Array

Day 5 Array


0238	Product of Array Except Self	Medium	Top_100_Liked_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n)	362	85.71
0560	Subarray Sum Equals K	Medium	Top_100_Liked_Questions, Array, Hash_Table, Prefix_Sum, Big_O_Time_O(n)_Space_O(n)	381	100.00

Day 6 String

Day 7 String


0763	Partition Labels	Medium	String, Hash_Table, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1)	286	100.00

Day 8 String


0049	Group Anagrams	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n)	339	66.67

Day 9 String


0005	Longest Palindromic Substring	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	337	100.00

Day 10 Linked List


0002	Add Two Numbers	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M))	353	88.68

Day 11 Linked List

Day 12 Linked List


0024	Swap Nodes in Pairs	Medium	Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1)	244	66.67

Day 13 Linked List


0025	Reverse Nodes in k-Group	Hard	Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k)	237	100.00

Day 14 Stack Queue


0155	Min Stack	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N)	385	100.00

Day 15 Tree


0105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Big_O_Time_O(N)_Space_O(N)	385	100.00

Day 16 Tree

Day 17 Tree


0230	Kth Smallest Element in a BST	Medium	Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n)	286	66.67

Day 18 Tree

Day 19 Graph

Day 20 Heap Priority Queue


0215	Kth Largest Element in an Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, Big_O_Time_O(n*log(n))_Space_O(log(n))	1341	100.00
0347	Top K Frequent Elements	Medium	Top_100_Liked_Questions, Array, Hash_Table, Sorting, Heap_Priority_Queue, Counting, Divide_and_Conquer, Quickselect, Bucket_Sort, Big_O_Time_O(n*log(n))_Space_O(k)	288	100.00

Day 21 Heap Priority Queue

Algorithm I

Day 1 Binary Search


0035	Search Insert Position	Easy	Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	228	100.00

Day 2 Two Pointers

Day 3 Two Pointers

Day 4 Two Pointers

Day 5 Two Pointers


0019	Remove Nth Node From End of List	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Big_O_Time_O(L)_Space_O(L)	275	100.00

Day 6 Sliding Window


0003	Longest Substring Without Repeating Characters	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1)	356	93.33

Day 7 Breadth First Search Depth First Search

Day 8 Breadth First Search Depth First Search

Day 9 Breadth First Search Depth First Search

Day 10 Recursion Backtracking


0021	Merge Two Sorted Lists	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n)	261	85.00
0206	Reverse Linked List	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1)	278	100.00

Day 11 Recursion Backtracking


0046	Permutations	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!)	225	100.00

Day 12 Dynamic Programming


0070	Climbing Stairs	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n)	255	100.00
0198	House Robber	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	249	100.00

Day 13 Bit Manipulation

Day 14 Bit Manipulation


0136	Single Number	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1)	295	100.00

Algorithm II

Day 1 Binary Search


0034	Find First and Last Position of Element in Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	1249	100.00
0033	Search in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	292	100.00
0074	Search a 2D Matrix	Medium	Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1)	253	100.00

Day 2 Binary Search


0153	Find Minimum in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N)	991	100.00

Day 3 Two Pointers


0015	3Sum	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2)	717	100.00

Day 4 Two Pointers


0011	Container With Most Water	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1)	620	93.33

Day 5 Sliding Window

Day 6 Breadth First Search Depth First Search


0200	Number of Islands	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(MN)_Space_O(MN)	463	100.00

Day 7 Breadth First Search Depth First Search

Day 8 Breadth First Search Depth First Search

Day 9 Recursion Backtracking


0078	Subsets	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Big_O_Time_O(2^n)_Space_O(n*2^n)	229	100.00

Day 10 Recursion Backtracking


0039	Combination Sum	Medium	Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n)	264	100.00

Day 11 Recursion Backtracking


0017	Letter Combinations of a Phone Number	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Big_O_Time_O(4^n)_Space_O(n)	279	100.00
0022	Generate Parentheses	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(2^n)_Space_O(n)	229	100.00
0079	Word Search	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Backtracking, Big_O_Time_O(4^(mn))_Space_O(mn)	1312	100.00

Day 12 Dynamic Programming


0055	Jump Game	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1)	437	100.00

Day 13 Dynamic Programming


0045	Jump Game II	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1)	299	100.00
0062	Unique Paths	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(mn)_Space_O(mn)	233	100.00

Day 14 Dynamic Programming


0005	Longest Palindromic Substring	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	337	100.00

Day 15 Dynamic Programming


0139	Word Break	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max)	263	100.00

Day 16 Dynamic Programming


0300	Longest Increasing Subsequence	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n)	259	100.00

Day 17 Dynamic Programming


1143	Longest Common Subsequence	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(nm)_Space_O(nm)	722	100.00

Day 18 Dynamic Programming


0072	Edit Distance	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2)	675	100.00
0322	Coin Change	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount)	1402	100.00

Day 19 Bit Manipulation

Day 20 Others

Day 21 Others

Binary Search I

Day 1

Day 2


0035	Search Insert Position	Easy	Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	228	100.00

Day 3

Day 4

Day 5


0034	Find First and Last Position of Element in Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	1249	100.00

Day 6

Day 7

Day 8


0074	Search a 2D Matrix	Medium	Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1)	253	100.00

Day 9

Day 10

Day 11


0033	Search in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	292	100.00

Day 12


0153	Find Minimum in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N)	991	100.00

Binary Search II

Day 1

Day 2

Day 3


0300	Longest Increasing Subsequence	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n)	259	100.00

Day 4

Day 5


0287	Find the Duplicate Number	Medium	Top_100_Liked_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Big_O_Time_O(n)_Space_O(n)	1322	100.00

Day 6

Day 7

Day 8

Day 9

Day 10

Day 11

Day 12

Day 13

Day 14

Day 15

Day 16

Day 17

Day 18

Day 19

Day 20

Dynamic Programming I

Day 1

Day 2


0070	Climbing Stairs	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n)	255	100.00

Day 3


0198	House Robber	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	249	100.00

Day 4


0055	Jump Game	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1)	437	100.00
0045	Jump Game II	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1)	299	100.00

Day 5


0053	Maximum Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1)	920	100.00

Day 6


0152	Maximum Product Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	322	100.00

Day 7


0121	Best Time to Buy and Sell Stock	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	797	30.00

Day 8

Day 9


0139	Word Break	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max)	263	100.00
0042	Trapping Rain Water	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1)	280	100.00

Day 10

Day 11


0096	Unique Binary Search Trees	Medium	Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(1)	285	100.00

Day 12

Day 13

Day 14

Day 15


0062	Unique Paths	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(mn)_Space_O(mn)	233	100.00

Day 16


0064	Minimum Path Sum	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(mn)_Space_O(mn)	285	100.00

Day 17


0005	Longest Palindromic Substring	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	337	100.00

Day 18


0300	Longest Increasing Subsequence	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n)	259	100.00

Day 19


1143	Longest Common Subsequence	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(nm)_Space_O(nm)	722	100.00
0072	Edit Distance	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2)	675	100.00

Day 20


0322	Coin Change	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount)	1402	100.00

Day 21

Programming Skills I

Day 1 Basic Data Type

Day 2 Operator

Day 3 Conditional Statements

Day 4 Loop

Day 5 Function

Day 6 Array

Day 7 Array

Day 8 String

Day 9 String

Day 10 Linked List and Tree


0104	Maximum Depth of Binary Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H)	254	100.00

Day 11 Containers and Libraries

Day 12 Class and Object

Programming Skills II

Day 1

Day 2

Day 3

Day 4

Day 5

Day 6


0739	Daily Temperatures	Medium	Top_100_Liked_Questions, Array, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(n)	955	100.00

Day 7

Day 8

Day 9

Day 10

Day 11


0049	Group Anagrams	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n)	339	66.67

Day 12

Day 13

Day 14

Day 15


0002	Add Two Numbers	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M))	353	88.68

Day 16

Day 17

Day 18


0155	Min Stack	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N)	385	100.00

Day 19

Day 20

Graph Theory I

Day 1 Matrix Related Problems


0200	Number of Islands	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(MN)_Space_O(MN)	463	100.00

Day 2 Matrix Related Problems

Day 3 Matrix Related Problems

Day 4 Matrix Related Problems

Day 5 Matrix Related Problems

Day 6 Matrix Related Problems

Day 7 Standard Traversal

Day 8 Standard Traversal

Day 9 Standard Traversal

Day 10 Standard Traversal

Day 11 Breadth First Search

Day 12 Breadth First Search

Day 13 Graph Theory

Day 14 Graph Theory

SQL I

Day 1 Select

Day 2 Select and Order

Day 3 String Processing Functions

Day 4 Union and Select

Day 5 Union

Day 6 Union

Day 7 Function

Day 8 Function

Day 9 Control of Flow

Day 10 Where

Level 1

Day 1 Prefix Sum

Day 2 String

Day 3 Linked List


0021	Merge Two Sorted Lists	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n)	261	85.00
0206	Reverse Linked List	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1)	278	100.00

Day 4 Linked List

Day 5 Greedy


0121	Best Time to Buy and Sell Stock	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	797	30.00

Day 6 Tree


0102	Binary Tree Level Order Traversal	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N)	252	100.00

Day 7 Binary Search

Day 8 Binary Search Tree


0098	Validate Binary Search Tree	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N))	239	100.00

Day 9 Graph/BFS/DFS


0200	Number of Islands	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(MN)_Space_O(MN)	463	100.00

Day 10 Dynamic Programming


0070	Climbing Stairs	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n)	255	100.00

Day 11 Dynamic Programming


0062	Unique Paths	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(mn)_Space_O(mn)	233	100.00

Day 12 Sliding Window/Two Pointer

Day 13 Hashmap


0001	Two Sum	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n)	261	94.89

Day 14 Stack


0394	Decode String	Medium	Top_100_Liked_Questions, String, Stack, Recursion, Big_O_Time_O(n)_Space_O(n)	268	100.00

Day 15 Heap

Algorithms

#	Title	Difficulty	Tag	Time, ms	Time, %
1143	Longest Common Subsequence	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Algorithm_II_Day_17_Dynamic_Programming, Dynamic_Programming_I_Day_19, Udemy_Dynamic_Programming, Big_O_Time_O(nm)_Space_O(nm)	722	100.00
0763	Partition Labels	Medium	String, Hash_Table, Greedy, Two_Pointers, Data_Structure_II_Day_7_String, Big_O_Time_O(n)_Space_O(1)	286	100.00
0739	Daily Temperatures	Medium	Top_100_Liked_Questions, Array, Stack, Monotonic_Stack, Programming_Skills_II_Day_6, Big_O_Time_O(n)_Space_O(n)	955	100.00
0647	Palindromic Substrings	Medium	String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n)	326	100.00
0560	Subarray Sum Equals K	Medium	Top_100_Liked_Questions, Array, Hash_Table, Prefix_Sum, Data_Structure_II_Day_5_Array, Big_O_Time_O(n)_Space_O(n)	381	100.00
0543	Diameter of Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Level_2_Day_7_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n)	264	100.00
0437	Path Sum III	Medium	Depth_First_Search, Tree, Binary_Tree, Level_2_Day_7_Tree, Big_O_Time_O(n)_Space_O(n)	336	100.00
0416	Partition Equal Subset Sum	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Level_2_Day_13_Dynamic_Programming, Big_O_Time_O(nsums)_Space_O(nsums)	1982	100.00
0394	Decode String	Medium	Top_100_Liked_Questions, String, Stack, Recursion, Level_1_Day_14_Stack, Udemy_Strings, Big_O_Time_O(n)_Space_O(n)	268	100.00
0347	Top K Frequent Elements	Medium	Top_100_Liked_Questions, Array, Hash_Table, Sorting, Heap_Priority_Queue, Counting, Divide_and_Conquer, Quickselect, Bucket_Sort, Data_Structure_II_Day_20_Heap_Priority_Queue, Big_O_Time_O(n*log(n))_Space_O(k)	288	100.00
0338	Counting Bits	Easy	Dynamic_Programming, Bit_Manipulation, Udemy_Bit_Manipulation, Big_O_Time_O(num)_Space_O(num)	330	100.00
0322	Coin Change	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Breadth_First_Search, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_20, Level_2_Day_12_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(amount)	1402	100.00
0300	Longest Increasing Subsequence	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Binary_Search, Algorithm_II_Day_16_Dynamic_Programming, Binary_Search_II_Day_3, Dynamic_Programming_I_Day_18, Udemy_Dynamic_Programming, Big_O_Time_O(n*log_n)_Space_O(n)	259	100.00
0287	Find the Duplicate Number	Medium	Top_100_Liked_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Binary_Search_II_Day_5, Big_O_Time_O(n)_Space_O(n)	1322	100.00
0239	Sliding Window Maximum	Hard	Top_100_Liked_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Udemy_Arrays, Big_O_Time_O(n*k)_Space_O(n+k)	1405	100.00
0238	Product of Array Except Self	Medium	Top_100_Liked_Questions, Array, Prefix_Sum, Data_Structure_II_Day_5_Array, Udemy_Arrays, Big_O_Time_O(n^2)_Space_O(n)	362	85.71
0234	Palindrome Linked List	Easy	Top_100_Liked_Questions, Two_Pointers, Stack, Linked_List, Recursion, Level_2_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1)	583	100.00
0230	Kth Smallest Element in a BST	Medium	Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_II_Day_17_Tree, Level_2_Day_9_Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n)	286	66.67
0226	Invert Binary Tree	Easy	Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_12_Tree, Level_2_Day_6_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n)	233	100.00
0215	Kth Largest Element in an Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, Data_Structure_II_Day_20_Heap_Priority_Queue, Big_O_Time_O(n*log(n))_Space_O(log(n))	1341	100.00
0208	Implement Trie (Prefix Tree)	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Level_2_Day_16_Design, Udemy_Trie_and_Heap, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N)	724	100.00
0206	Reverse Linked List	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_8_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1)	278	100.00
0200	Number of Islands	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Algorithm_II_Day_6_Breadth_First_Search_Depth_First_Search, Graph_Theory_I_Day_1_Matrix_Related_Problems, Level_1_Day_9_Graph/BFS/DFS, Udemy_Graph, Big_O_Time_O(MN)_Space_O(MN)	463	100.00
0198	House Robber	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_3, Level_2_Day_12_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	249	100.00
0169	Majority Element	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Data_Structure_II_Day_1_Array, Udemy_Famous_Algorithm, Big_O_Time_O(n)_Space_O(1)	278	100.00
0155	Min Stack	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Data_Structure_II_Day_14_Stack_Queue, Programming_Skills_II_Day_18, Level_2_Day_16_Design, Udemy_Design, Big_O_Time_O(1)_Space_O(N)	385	100.00
0153	Find Minimum in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Array, Binary_Search, Algorithm_II_Day_2_Binary_Search, Binary_Search_I_Day_12, Udemy_Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N)	991	100.00
0152	Maximum Product Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Dynamic_Programming_I_Day_6, Level_2_Day_13_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(N)_Space_O(1)	322	100.00
0148	Sort List	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Level_2_Day_4_Linked_List, Big_O_Time_O(log(N))_Space_O(log(N))	489	100.00
0139	Word Break	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Algorithm_II_Day_15_Dynamic_Programming, Dynamic_Programming_I_Day_9, Udemy_Dynamic_Programming, Big_O_Time_O(M+max*N)_Space_O(M+N+max)	263	100.00
0136	Single Number	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Data_Structure_II_Day_1_Array, Algorithm_I_Day_14_Bit_Manipulation, Udemy_Integers, Big_O_Time_O(N)_Space_O(1)	295	100.00
0131	Palindrome Partitioning	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(N2^N)_Space_O(2^NN)	398	100.00
0128	Longest Consecutive Sequence	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Big_O_Time_O(N_log_N)_Space_O(1)	669	100.00
0124	Binary Tree Maximum Path Sum	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N)	291	100.00
0121	Best Time to Buy and Sell Stock	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Data_Structure_I_Day_3_Array, Dynamic_Programming_I_Day_7, Level_1_Day_5_Greedy, Udemy_Arrays, Big_O_Time_O(N)_Space_O(1)	797	30.00
0105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Big_O_Time_O(N)_Space_O(N)	385	100.00
0104	Maximum Depth of Binary Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Programming_Skills_I_Day_10_Linked_List_and_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(H)	254	100.00
0102	Binary Tree Level Order Traversal	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_1_Day_6_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N)	252	100.00
0101	Symmetric Tree	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_2_Day_15_Tree, Big_O_Time_O(N)_Space_O(log(N))	255	60.00
0098	Validate Binary Search Tree	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_I_Day_14_Tree, Level_1_Day_8_Binary_Search_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(log(N))	239	100.00
0096	Unique Binary Search Trees	Medium	Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Dynamic_Programming_I_Day_11, Big_O_Time_O(n)_Space_O(1)	285	100.00
0094	Binary Tree Inorder Traversal	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Data_Structure_I_Day_10_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n)	225	100.00
0079	Word Search	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Big_O_Time_O(4^(mn))_Space_O(mn)	1312	100.00
0078	Subsets	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Algorithm_II_Day_9_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n*2^n)	229	100.00
0074	Search a 2D Matrix	Medium	Top_100_Liked_Questions, Array, Binary_Search, Matrix, Data_Structure_I_Day_5_Array, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_8, Level_2_Day_8_Binary_Search, Udemy_2D_Arrays/Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1)	253	100.00
0072	Edit Distance	Medium	Top_100_Liked_Questions, String, Dynamic_Programming, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_19, Udemy_Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2)	675	100.00
0070	Climbing Stairs	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_2, Level_1_Day_10_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(n)_Space_O(n)	255	100.00
0064	Minimum Path Sum	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Udemy_Dynamic_Programming, Big_O_Time_O(mn)_Space_O(mn)	285	100.00
0062	Unique Paths	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_15, Level_1_Day_11_Dynamic_Programming, Big_O_Time_O(mn)_Space_O(mn)	233	100.00
0056	Merge Intervals	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Data_Structure_II_Day_2_Array, Level_2_Day_17_Interval, Udemy_2D_Arrays/Matrix, Big_O_Time_O(n_log_n)_Space_O(n)	305	100.00
0055	Jump Game	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Algorithm_II_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_4, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1)	437	100.00
0053	Maximum Subarray	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Data_Structure_I_Day_1_Array, Dynamic_Programming_I_Day_5, Udemy_Famous_Algorithm, Big_O_Time_O(n)_Space_O(1)	920	100.00
0051	N-Queens	Hard	Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(N!)_Space_O(N)	291	100.00
0049	Group Anagrams	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Data_Structure_II_Day_8_String, Programming_Skills_II_Day_11, Udemy_Strings, Big_O_Time_O(n*k_log_k)_Space_O(n)	339	66.67
0046	Permutations	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Algorithm_I_Day_11_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(n*n!)_Space_O(n+n!)	225	100.00
0045	Jump Game II	Medium	Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_4, Big_O_Time_O(n)_Space_O(1)	299	100.00
0042	Trapping Rain Water	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Dynamic_Programming_I_Day_9, Udemy_Two_Pointers, Big_O_Time_O(n)_Space_O(1)	280	100.00
0041	First Missing Positive	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n)	806	100.00
0039	Combination Sum	Medium	Top_100_Liked_Questions, Array, Backtracking, Algorithm_II_Day_10_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n+2^n)	264	100.00
0035	Search Insert Position	Easy	Top_100_Liked_Questions, Array, Binary_Search, Algorithm_I_Day_1_Binary_Search, Binary_Search_I_Day_2, Big_O_Time_O(log_n)_Space_O(1)	228	100.00
0034	Find First and Last Position of Element in Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_5, Big_O_Time_O(log_n)_Space_O(1)	1249	100.00
0033	Search in Rotated Sorted Array	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_11, Level_2_Day_8_Binary_Search, Udemy_Binary_Search, Big_O_Time_O(log_n)_Space_O(1)	292	100.00
0032	Longest Valid Parentheses	Hard	Top_100_Liked_Questions, String, Dynamic_Programming, Stack, Big_O_Time_O(n)_Space_O(1)	277	100.00
0025	Reverse Nodes in k-Group	Hard	Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_13_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(k)	237	100.00
0024	Swap Nodes in Pairs	Medium	Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_12_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1)	244	66.67
0023	Merge k Sorted Lists	Medium	Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_12_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1)	215	100.00
0022	Generate Parentheses	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n)	229	100.00
0021	Merge Two Sorted Lists	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_7_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(m+n)_Space_O(m+n)	261	85.00
0020	Valid Parentheses	Easy	Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Data_Structure_I_Day_9_Stack_Queue, Udemy_Strings, Big_O_Time_O(n)_Space_O(n)	252	81.48
0019	Remove Nth Node From End of List	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Algorithm_I_Day_5_Two_Pointers, Level_2_Day_3_Linked_List, Big_O_Time_O(L)_Space_O(L)	275	100.00
0017	Letter Combinations of a Phone Number	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(4^n)_Space_O(n)	279	100.00
0015	3Sum	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Data_Structure_II_Day_1_Array, Algorithm_II_Day_3_Two_Pointers, Udemy_Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2)	717	100.00
0011	Container With Most Water	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Algorithm_II_Day_4_Two_Pointers, Big_O_Time_O(n)_Space_O(1)	620	93.33
0010	Regular Expression Matching	Hard	Top_Interview_Questions, String, Dynamic_Programming, Recursion, Udemy_Dynamic_Programming, Big_O_Time_O(mn)_Space_O(mn)	296	100.00
0009	Palindrome Number	Easy	Math, Udemy_Integers	1007	87.50
0008	String to Integer (atoi)	Medium	Top_Interview_Questions, String	352	55.56
0007	Reverse Integer	Medium	Top_Interview_Questions, Math, Udemy_Integers	317	100.00
0006	Zigzag Conversion	Medium	String	421	100.00
0005	Longest Palindromic Substring	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Data_Structure_II_Day_9_String, Algorithm_II_Day_14_Dynamic_Programming, Dynamic_Programming_I_Day_17, Udemy_Strings, Big_O_Time_O(n)_Space_O(n)	337	100.00
0004	Median of Two Sorted Arrays	Hard	Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Divide_and_Conquer, Big_O_Time_O(log(min(N,M)))_Space_O(1)	474	86.21
0003	Longest Substring Without Repeating Characters	Medium	Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Algorithm_I_Day_6_Sliding_Window, Level_2_Day_14_Sliding_Window/Two_Pointer, Udemy_Strings, Big_O_Time_O(n)_Space_O(1)	356	93.33
0002	Add Two Numbers	Medium	Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Data_Structure_II_Day_10_Linked_List, Programming_Skills_II_Day_15, Big_O_Time_O(max(N,M))_Space_O(max(N,M))	353	88.68
0001	Two Sum	Easy	Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Data_Structure_I_Day_2_Array, Level_1_Day_13_Hashmap, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n)	261	94.89

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src/main/elixir		src/main/elixir
LICENSE		LICENSE
README.md		README.md

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Level 2

Day 1 Implementation/Simulation

Day 2 String

Day 3 Linked List

Day 4 Linked List

Day 5 Greedy

Day 6 Tree

Day 7 Tree

Day 8 Binary Search

Day 9 Binary Search Tree

Day 10 Graph/BFS/DFS

Day 11 Graph/BFS/DFS

Day 12 Dynamic Programming

Day 13 Dynamic Programming

Day 14 Sliding Window/Two Pointer

Day 15 Tree

Day 16 Design

Day 17 Interval

Day 18 Stack

Day 19 Union Find

Day 20 Brute Force/Backtracking

Udemy

Udemy Integers

Udemy Strings

Udemy Binary Search

Udemy Arrays

Udemy Two Pointers

Udemy Famous Algorithm

Udemy Sorting Algorithms

Udemy 2D Arrays/Matrix

Udemy Linked List

Udemy Tree Stack Queue

Udemy Trie and Heap

Udemy Graph

Udemy Dynamic Programming

Udemy Backtracking/Recursion

Udemy Bit Manipulation

Udemy Design

Data Structure I

Day 1 Array

Day 2 Array

Day 3 Array

Day 4 Array

Day 5 Array

Day 6 String

Day 7 Linked List

Day 8 Linked List

Day 9 Stack Queue

Day 10 Tree

Day 11 Tree

Day 12 Tree

Day 13 Tree

Day 14 Tree

Data Structure II

Day 1 Array

Day 2 Array

Day 3 Array

Day 4 Array

Day 5 Array

Day 6 String

Day 7 String

Day 8 String

Day 9 String

Day 10 Linked List

Day 11 Linked List

Day 12 Linked List

Day 13 Linked List

Day 14 Stack Queue

Day 15 Tree

Day 16 Tree

Day 17 Tree

Day 18 Tree

Day 19 Graph

Day 20 Heap Priority Queue