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Problems explorer

Browse by topic · auto-judge · company sheets · roadmaps — not just a problem dump.

472 problems in this topic

# Title Topics Acceptance Pts Difficulty
201 Meeting Rooms II — 30 Medium Solve
202 Merge Two Sorted Lists — 20 Easy Solve
203 Missing Number — 20 Easy Solve
204 Serialize and Deserialize Binary Tree — 40 Hard Solve
205 Valid Anagram — 20 Easy Solve
206 Walls and Gates — 30 Medium Solve
207 Add Two Numbers — 30 Medium Solve
208 Alien Dictionary — 40 Hard Solve
209 Graph Valid Tree — 30 Medium Solve
210 Implement Trie (Prefix Tree) — 30 Medium Solve
211 Invert Binary Tree — 20 Easy Solve
212 Kth Largest Element in an Array — 30 Medium Solve
213 Kth Smallest Element in a BST — 30 Medium Solve
214 Kth Smallest Element in a BST — 30 Medium Solve
215 Meeting Rooms — 20 Easy Solve
216 Missing Number — 20 Easy Solve
217 Reverse Linked List — 20 Easy Solve
218 Reverse Nodes in k-Group — 40 Hard Solve
219 Valid Anagram — 20 Easy Solve
220 Walls and Gates — 30 Medium Solve
221 Alien Dictionary — 40 Hard Solve
222 Contains Duplicate — 20 Easy Solve
223 Course Schedule II — 30 Medium Solve
224 Find the Duplicate Number — 30 Medium Solve
225 Happy Number — 20 Easy Solve
226 Invert Binary Tree — 20 Easy Solve
227 Lowest Common Ancestor of a Binary Search Tree — 30 Medium Solve
228 Meeting Rooms II — 30 Medium Solve
229 Merge k Sorted Lists — 40 Hard Solve
230 Missing Number — 20 Easy Solve
231 Product of Array Except Self — 30 Medium Solve
232 Valid Anagram — 20 Easy Solve
233 Valid Parentheses — 20 Easy Solve
234 Walls and Gates — 30 Medium Solve
235 Add Two Numbers — 30 Medium Solve
236 Alien Dictionary — 40 Hard Solve
237 Design Add and Search Words Data Structure — 30 Medium Solve
238 Encode and Decode Strings — 30 Medium Solve
239 Happy Number — 20 Easy Solve
240 Invert Binary Tree — 20 Easy Solve
241 Kth Smallest Element in a BST — 30 Medium Solve
242 Meeting Rooms II — 30 Medium Solve
243 Merge Two Sorted Lists — 20 Easy Solve
244 Number of Islands — 30 Medium Solve
245 Product of Array Except Self — 30 Medium Solve
246 Serialize and Deserialize Binary Tree — 40 Hard Solve
247 Valid Parentheses — 20 Easy Solve
248 Word Search II — 40 Hard Solve
249 Alien Dictionary — 40 Hard Solve
250 Course Schedule — 30 Medium Solve
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