763 problems · Solve with AI-powered hints & explanations
| # | Title | Difficulty |
|---|---|---|
| 206 | Reverse Linked List | Easy |
| 217 | Contains Duplicate | Easy |
| 219 | Contains Duplicate II |
Page 2 of 16
| Easy |
| 222 | Count Complete Tree Nodes | Easy |
| 225 | Implement Stack using Queues | Easy |
| 226 | Invert Binary Tree | Easy |
| 228 | Summary Ranges | Easy |
| 231 | Power of Two | Easy |
| 232 | Implement Queue using Stacks | Easy |
| 234 | Palindrome Linked List | Easy |
| 242 | Valid Anagram | Easy |
| 257 | Binary Tree Paths | Easy |
| 258 | Add Digits | Easy |
| 263 | Ugly Number | Easy |
| 268 | Missing Number | Easy |
| 278 | First Bad Version | Easy |
| 283 | Move Zeroes | Easy |
| 290 | Word Pattern | Easy |
| 292 | Nim Game | Easy |
| 303 | Range Sum Query - Immutable | Easy |
| 326 | Power of Three | Easy |
| 338 | Counting Bits | Easy |
| 342 | Power of Four | Easy |
| 344 | Reverse String | Easy |
| 345 | Reverse Vowels of a String | Easy |
| 349 | Intersection of Two Arrays | Easy |
| 350 | Intersection of Two Arrays II | Easy |
| 367 | Valid Perfect Square | Easy |
| 374 | Guess Number Higher or Lower | Easy |
| 383 | Ransom Note | Easy |
| 387 | First Unique Character in a String | Easy |
| 389 | Find the Difference | Easy |
| 392 | Is Subsequence | Easy |
| 401 | Binary Watch | Easy |
| 404 | Sum of Left Leaves | Easy |
| 405 | Convert a Number to Hexadecimal | Easy |
| 409 | Longest Palindrome | Easy |
| 412 | Fizz Buzz | Easy |
| 414 | Third Maximum Number | Easy |
| 415 | Add Strings | Easy |
| 434 | Number of Segments in a String | Easy |
| 441 | Arranging Coins | Easy |
| 448 | Find All Numbers Disappeared in an Array | Easy |
| 455 | Assign Cookies | Easy |
| 459 | Repeated Substring Pattern | Easy |
| 461 | Hamming Distance | Easy |
| 463 | Island Perimeter | Easy |
| 476 | Number Complement | Easy |
| 482 | License Key Formatting | Easy |
| 485 | Max Consecutive Ones | Easy |
© 2026 PhantomCodeAI. All rights reserved.