| 218 | The Skyline Problem | Hard |
| 239 | Sliding Window Maximum | Hard |
| 295 | Find Median from Data Stream | Hard |
| 347 | Top K Frequent Elements | Medium |
| 355 | Design Twitter | Medium |
| 373 | Find K Pairs with Smallest Sums | Medium |
| 407 | Trapping Rain Water II | Hard |
| 420 | Strong Password Checker | Hard |
| 451 | Sort Characters By Frequency | Medium |
| 480 | Sliding Window Median | Hard |
| 502 | IPO | Hard |
| 506 | Relative Ranks | Easy |
| 621 | Task Scheduler | Medium |
| 630 | Course Schedule III | Hard |
| 632 | Smallest Range Covering Elements from K Lists | Hard |
| 658 | Find K Closest Elements | Medium |
| 659 | Split Array into Consecutive Subsequences | Medium |
| 675 | Cut Off Trees for Golf Event | Hard |
| 692 | Top K Frequent Words | Medium |
| 703 | Kth Largest Element in a Stream | Easy |
| 743 | Network Delay Time | Medium |
| 767 | Reorganize String | Medium |
| 778 | Swim in Rising Water | Hard |
| 786 | K-th Smallest Prime Fraction | Medium |
| 787 | Cheapest Flights Within K Stops | Medium |
| 857 | Minimum Cost to Hire K Workers | Hard |
| 862 | Shortest Subarray with Sum at Least K | Hard |
| 871 | Minimum Number of Refueling Stops | Hard |
| 882 | Reachable Nodes In Subdivided Graph | Hard |
| 912 | Sort an Array | Medium |