My Competitive Programming Problems
All the competitive programming problems I’ve (co)authored as of December 2022, excluding USACO Camp. More on the way …
USA Computing Olympiad #
Total: 67
See this page if you’re interested in problemsetting for the USACO.
Bronze #
Total: 6
- 2020 January: Photoshoot (Benjamin Qi and Chris Zhang)
- 2020 December: Do You Know Your ABCs? (Benjamin Qi)
- 2021 February: Comfortable Cows (Benjamin Qi)
- 2021 US Open: Acowdemia III (Benjamin Qi)
- 2022 February: Photoshoot 2 (Benjamin Qi)
- 2022 December: Reverse Engineering (Benjamin Qi)
Silver #
Total: 9
- 2019 December: Meetings (Benjamin Qi)
- 2020 December: Rectangular Pasture (Benjamin Qi)
- 2021 February: Comfortable Cows (Benjamin Qi)
- 2021 US Open: Do You Know Your ABCs? (Benjamin Qi)
- 2021 December: Convoluted Intervals (Benjamin Qi)
- 2022 February: Redistributing Gifts (Benjamin Qi)
- 2022 US Open: Visits (Benjamin Qi and Michael Cao)
- 2023 January: Find and Replace (Benjamin Qi)
- 2023 January: Following Directions (Benjamin Qi)
Gold #
Total: 23
- 2020 February: Help Yourself (Benjamin Qi)
- 2020 US Open: Favorite Colors (William Lin and Benjamin Qi)
- 2020 US Open: Exercise (Benjamin Qi)
- 2020 December: Replication (Benjamin Qi)
- 2020 December: Bovine Genetics (Benjamin Qi)
- 2020 December: Square Pasture (Benjamin Qi)
- 2021 February: Stone Game (Benjamin Qi)
- 2021 February: Modern Art 3 (Brian Dean and Benjamin Qi)
- 2021 February: Count the Cows (Benjamin Qi)
- 2021 US Open: United Cows of Farmer John (Benjamin Qi)
- 2021 US Open: Portals (Benjamin Qi)
- 2021 US Open: Permutation (Benjamin Qi)
- 2021 December: Paired Up (Benjamin Qi)
- 2022 January: Drought (Arpan Banerjee and Benjamin Qi)
- 2022 January: Farm Updates (Benjamin Qi)
- 2022 February: Redistributing Gifts (Benjamin Qi)
- 2022 February: Cow Camp (Benjamin Qi)
- 2022 US Open: Apple Catching (Benjamin Qi)
- 2022 US Open: Pair Programming (Benjamin Qi)
- 2022 December: Strongest Friendship Group (Benjamin Qi)
- 2023 January: Find and Replace (Benjamin Qi)
- 2023 January: Lights Off (William Yue, Eric Yang, and Benjamin Qi)
- 2023 January: Moo Route (Brandon Wang, Claire Zhang, and Benjamin Qi)
Platinum #
Total: 29
- 2019 December: Greedy Pie Eaters (Benjamin Qi)
- 2019 December: Bessie’s Snow Cow (Michael Cao and Benjamin Qi)
- 2020 January: Non-Decreasing Subsequences (Benjamin Qi)
- 2020 February: Equilateral Triangles (Benjamin Qi)
- 2020 February: Help Yourself (Benjamin Qi)
- 2020 US Open: Sprinklers 2: Return of the Alfalfa (Benjamin Qi)
- 2020 US Open: Exercise (Benjamin Qi)
- 2020 December: Spaceship (Benjamin Qi)
- 2020 December: Cowmistry (Benjamin Qi)
- 2021 January: Sum of Distances (Benjamin Qi)
- 2021 January: Minimum Cost Paths (Benjamin Qi)
- 2021 February: No Time to Dry (Andi Qu, Brian Dean, and Benjamin Qi)
- 2021 February: Minimizing Edges (Benjamin Qi)
- 2021 February: Counting Graphs (Benjamin Qi)
- 2021 US Open: United Cows of Farmer John (Benjamin Qi)
- 2021 US Open: Routing Schemes (Benjamin Qi)
- 2021 US Open: Balanced Subsets (Benjamin Qi)
- 2021 December: Tickets (Benjamin Qi)
- 2021 December: Paired Up (Benjamin Qi)
- 2022 January: Minimizing Haybales (Daniel Zhang and Benjamin Qi)
- 2022 January: Multiple Choice Test (Benjamin Qi)
- 2022 February: Sleeping in Class (Jesse Choe and Benjamin Qi)
- 2022 US Open: 262144 Revisited (Benjamin Qi)
- 2022 December: Breakdown (Benjamin Qi)
- 2022 December: Making Friends (Benjamin Qi)
- 2022 December: Palindromes (Mythreya Dharani and Benjamin Qi)
- 2023 January: Tractor Paths (Benjamin Qi)
- 2023 January: Mana Collection (Benjamin Qi)
- 2023 January: Subtree Activation (Benjamin Qi)
Other #
Total: 2
- European Girls’ Olympiad in Informatics 2021: Lanterns (Benjamin Qi, Richard Qi, and Siyong Huang)
- Codeforces Round 736 Div 1 E: Gregor and the Two Painters (Benjamin Qi)