| 1 | Two Sum | Python | Easy | O(n) | O(n) | |
| 2 | Add Two Numbers | Python | Medium | O(n) | O(n) | |
| 3 | Longest Substring Without Repeating Characters | Python | Medium | O(n) | O(n) | |
| 5 | Longest Palindromic Substring | Python | Medium | O(n^2) | O(n) | |
| 7 | Reverse Integer | Python | Easy | O(log(n)) | O(1) | |
| 15 | 3sum | Python | Medium | O(n^2) | O(n) | |
| 16 | 3Sum Closest | Python | Medium | O(n^2) | O(n) | |
| 17 | Letter Combinations of a Phone Number | Python | Medium | O(4^n) | O(4^n) | |
| 19 | Remove Nth Node From End of List | Python | Medium | O(n) | O(1) | |
| 21 | Merge Two Sorted Lists | Python | Easy | O(n) | O(1) | |
| 22 | Generate Parentheses | Python | Medium | O(4^n / sqrt(n)) | O(4^n / sqrt(n)) | |
| 31 | Next Permutation | Python | Medium | O(n) | O(1) | |
| 33 | Search in Rotated Sorted Array | Python | Medium | O(log(n)) | O(1) | |
| 43 | Multiply Strings | Python | Medium | O(n*m) | O(n + m) | |
| 56 | Merge Intervals | Python | Medium | O(n*log(n)) | O(n) Result array | |
| 64 | Minimum Path Sum | Python | Medium | O(n*m) | O(n*m) | |
| 98 | Validate Binary Search Tree | Python | Medium | O(n) | O(depth) | |
| 116 | Populating Next Right Pointers in Each Node | Python | Medium | O(n) | O(log(depth)) | |
| 124 | Binary Tree Maximum Path Sum | Python | Hard | O(n) | O(d) where d = tree depth (worst case also n) | |
| 152 | Maximum Product Subarray | Python | Medium | O(n) | O(1) | |
| 159 | Longest Substring with At Most Two Distinct Characters | Python | Medium | O(n) | O(1) | |
| 188 | Best Time to Buy and Sell Stock IV | Python | Hard | O(n*k) | O(n*k) | |
| 198 | House Robber | Python | Medium | O(n) | O(1) | |
| 200 | Number of Islands | Python | Medium | O(n*m) | O(n*m) | |
| 213 | House Robber II | Python | Medium | O(n) | O(1) | |
| 246 | Strobogrammatic Number | Python | Easy | O(n) | O(1) | |
| 247 | Strobogrammatic Number II | Python | Medium | O(5^n) | O(5^n) | |
| 300 | Longest Increasing Subsequence | Python | Medium | O(n*log(n)) | O(n) | |
| 322 | Coin Change | Python | Medium | O(m * n) | O(m) | |
| 410 | Split Array Largest Sum | Python | Hard | O(n^2 * m) | O(n * m) | |
| 418 | Sentence Screen Fitting | Python | Medium | O(~r * c ) | O(w) | |
| 460 | LFU Cache | Python | Hard | O(1) for getting and setting | O(n)-ish | |
| 492 | License Key Formatting | Python | Easy | O(n) | O(n) | |
| 543 | Diameter of Binary Tree | Python | Easy | O(n) | O(d) | |
| 547 | Number of Provinces | Python | Medium | O(n^2) | O(n) | |
| 560 | Subarray Sum Equals K | Python | Medium | O(n) | O(n) | |
| 593 | Valid Square | Python | Medium | O(1) | O(1) | |
| 616 | Add Bold Tag in String | Python | Mediun | O(w + n*m) | O(w + n) | |
| 647 | Palindromic Substrings | Python | Medium | O(n^2) | O(1) | |
| 652 | Find Duplicate Subtrees | Python | Medium | O(n^2) | O(n^2) | |
| 731 | My Calendar II | Python | Medium | O(n^2) | O(n) | |
| 777 | Swap Adjacent in LR String | Python | Medium | O(n) | O(n) | |
| 792 | Number of Matching Subsequences | Python | Medium | O(n * m) | O(m) | |
| 829 | Consecutive Numbers Sum | Python | Hard | O(N^(1/2)) | O(1) | |
| 833 | Find And Replace in String | Python | Medium | O(n) | O(n) | |
| 844 | Backspace String Compare | Python | Easy | O(n) | O(n) | |
| 852 | Peak Index in a Mountain Array | Python | Easy | O(log(n)) | O(1) | |
| 876 | Middle of the Linked List | Python | Easy | O(n) | O(1) | |
| 904 | Fruit Into Baskets | Python | Medium | O(n) | O(1) | |
| 929 | Unique Email Addresses | Python | Easy | O(n) | O(n) | |
| 935 | Knight Dialer | Python | Medium | O(n) | O(1) | |
| 937 | Reorder Data in Log Files | Python | Easy | O(n*log(n)) | O(n) | |
| 939 | Minimum Area Rectangle | Python | Medium | O(n^2) | O(n) | |
| 987 | Vertical Order Traversal of a Binary Tree | Python | Hard | O(n * log(n)) | O(n) | |
| 1029 | Two City Scheduling | Python | Medium | O(n * log(n)) | O(n) | |
| 1041 | Robot Bounded In Circle | Python | Medium | O(n) | O(1) | |
| 1074 | Number of Submatrices That Sum to Target | Python | Hard | O(n^2*m) | O(n*m) | |
| 1110 | Delete Nodes And Return Forest | Python | Medium | O(n) | O(n) | |
| 1136 | Parallel Courses | Python | Medium | O(V + E) | O(V + E) | |
| 1167 | Minimum Cost to Connect Sticks | Python | Medium | O(n*log(n)) | O(n) | |
| 1396 | Design Underground System | Python | Medium | O(1) | O(n) | |
| 1465 | Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts | Python | Medium | O(n*log(n)) | O(n) | |
| 1472 | Design Browser History | Python | Medium | ~O(1) | O(n) | |
| 1499 | Max Value of Equation | Python | Hard | O(n*log(n)) | O(n) | |
| 1525 | Number of Good Ways to Split a String | Python | Medium | O(n) | O(n) | |
| 1548 | The Most Similar Path in a Graph | Python | Hard | O(n*m*E) | O(n*m) | |
| 1648 | Sell Diminishing-Valued Colored Balls | Python | Medium | O(n* log(n)) | O(n) | |
| 1725 | Number Of Rectangles That Can Form The Largest Square | Python | Easy | O(n) | O(1) | |
| 1726 | Tuple with Same Product | Python | Medium | O(n^2) | O(n^2) | |
| 1727 | Largest Submatrix With Rearrangements | Python | Medium | O(nmlog(m)) | O(n*m) | |
| 1776 | Car Fleet II | Python | Hard | O(n) | O(n) | |
| 1891 | Cutting Ribbons | Python | Medium | O(n*log(max(n))) | O(1) | |