| 778 | Swim in Rising Water | Hard |
| 780 | Reaching Points | Hard |
| 782 | Transform to Chessboard | Hard |
| 793 | Preimage Size of Factorial Zeroes Function | Hard |
| 798 | Smallest Rotation with Highest Score | Hard |
| 801 | Minimum Swaps To Make Sequences Increasing | Hard |
| 803 | Bricks Falling When Hit | Hard |
| 805 | Split Array With Same Average | Hard |
| 810 | Chalkboard XOR Game | Hard |
| 815 | Bus Routes | Hard |
| 818 | Race Car | Hard |
| 827 | Making A Large Island | Hard |
| 828 | Count Unique Characters of All Substrings of a Given String | Hard |
| 829 | Consecutive Numbers Sum | Hard |
| 834 | Sum of Distances in Tree | Hard |
| 839 | Similar String Groups | Hard |
| 843 | Guess the Word | Hard |
| 850 | Rectangle Area II | Hard |
| 854 | K-Similar Strings | Hard |
| 857 | Minimum Cost to Hire K Workers | Hard |
| 862 | Shortest Subarray with Sum at Least K | Hard |
| 864 | Shortest Path to Get All Keys | Hard |
| 871 | Minimum Number of Refueling Stops | Hard |
| 877 | Shortest Path Visiting All Nodes | Hard |
| 878 | Nth Magical Number | Hard |
| 879 | Profitable Schemes | Hard |
| 882 | Reachable Nodes In Subdivided Graph | Hard |
| 887 | Super Egg Drop | Hard |
| 891 | Sum of Subsequence Widths | Hard |
| 895 | Maximum Frequency Stack | Hard |