| 70. Climbing Stairs | | | Solve | Easy | | |
| 74. Search a 2D Matrix | | | Solve | Medium | | |
| 75. Sort Colors | | | Solve | Medium | | |
| 76. Minimum Window Substring | | | Solve | Hard | | |
| 77. Combinations | | | Solve | Medium | | |
| 78. Subsets | | | Solve | Medium | | |
| 80. Remove Duplicates from Sorted Array II | | | Solve | Medium | | |
| 81. Search in Rotated Sorted Array II | | | Solve | Medium | | |
| 83. Remove Duplicates from Sorted List | | | Solve | Easy | | |
| 84. Largest Rectangle in Histogram | | | Solve | Hard | | |
| 86. Partition List | | | Solve | Medium | | |
| 90. Subsets II | | | Solve | Medium | | |
| 92. Reverse Linked List II | | | Solve | Medium | | |
| 94. Binary Tree Inorder Traversal | | | Solve | Easy | | |
| 95. Unique Binary Search Trees II | | | Solve | Medium | | |
| 98. Validate Binary Search Tree | | | Solve | Medium | | |
| 99. Recover Binary Search Tree | | | Solve | Medium | | |
| 101. Symmetric Tree | | | Solve | Easy | | |
| 103. Binary Tree Zigzag Level Order Traversal | | | Solve | Medium | | |
| 110. Balanced Binary Tree | | | Solve | Easy | | |
| 116. Populating Next Right Pointers in Each Node | | | Solve | Medium | | |
| 117. Populating Next Right Pointers in Each Node II | | | Solve | Medium | | |
| 118. Pascal's Triangle | | | Solve | Easy | | |
| 119. Pascal's Triangle II | | | Solve | Easy | | |
| 121. Best Time to Buy and Sell Stock | | | Solve | Easy | | |
| 124. Binary Tree Maximum Path Sum | | | Solve | Hard | | |
| 125. Valid Palindrome | | | Solve | Easy | | |
| 127. Word Ladder | | | Solve | Hard | | |
| 128. Longest Consecutive Sequence | | | Solve | Medium | | |
| 134. Gas Station | | | Solve | Medium | | |
| 135. Candy | | | Solve | Hard | | |
| 136. Single Number | | | Solve | Easy | | |
| 138. Copy List with Random Pointer | | | Solve | Medium | | |
| 139. Word Break | | | Solve | Medium | | |
| 140. Word Break II | | | Solve | Hard | | |
| 141. Linked List Cycle | | | Solve | Easy | 42gearMobilitySystems+131 | |
| 143. Reorder List | | | Solve | Medium | | |
| 144. Binary Tree Preorder Traversal | | | Solve | Easy | | |
| 146. LRU Cache | | | Solve | Medium | | |
| 152. Maximum Product Subarray | | | Solve | Medium | | |
| 153. Find Minimum in Rotated Sorted Array | | | Solve | Medium | | |
| 155. Min Stack | | | Solve | Medium | | |
| 160. Intersection of Two Linked Lists | | | Solve | Easy | | |
| 167. Two Sum II - Input Array Is Sorted | | | Solve | Medium | | |
| 168. Excel Sheet Column Title | | | Solve | Easy | | |
| 169. Majority Element | | | Solve | Easy | | |
| 175. Combine Two Tables | | | Solve | Easy | | |
| 176. Second Highest Salary | | | Solve | Medium | | |
| 177. Nth Highest Salary | | | Solve | Medium | | |
| 178. Rank Scores | | | Solve | Medium | | |