| Problem Name | Online Judge | Year | Contest | Difficulty Level | |
|---|---|---|---|---|---|
| 1 | Building Bridges | Live Archive | 2003 | World Finals - Beverly Hills | 1 |
| 2 | Tourist Guide | UVA | 1 | ||
| 3 | Network | UVA | 1 | ||
| 4 | Network | TJU | 1 | ||
| 5 | Submerging Islands | SPOJ | 1 | ||
| 6 | VOI 2015 Day 1 - Kế hoạch cải tổ | SPOJ Vietnam | 3 | ||
| 7 | Police Query | SPOJ | 3 | ||
| 8 | Cutting Figure | Codeforces | Codeforces Round #122 (Div. 1) & Codeforces Round #122 (Div. 2) | 5 |