| Problem Name | Online Judge | Contest | Difficulty Level | |
|---|---|---|---|---|
| 1 | Street Parade | SPOJ | 1 | |
| 2 | Team Queue | UVA | 1 | |
| 3 | Group Reverse | UVA | 1 | |
| 4 | Error Correction | UVA | 1 | |
| 5 | Exams | Codeforces | Codeforces Round #274 (Div. 2) & Codeforces Round #274 (Div. 1) | 1 |
| 6 | Laptops | Codeforces | Codeforces Round #260 (Div. 2) | 1 |
| 7 | Mass of Molecule | SPOJ | 1 | |
| 8 | Queue | Codeforces | Codeforces Round #303 (Div. 2) | 1 |
| 9 | Box of Bricks | UVA | 1 | |
| 10 | WERTYU | UVA | 1 | |
| 11 | Rails | UVA | 1 | |
| 12 | Transform the Expression | SPOJ | 1 | |
| 13 | Army Buddies | UVA | 1 | |
| 14 | Adding Reversed Numbers | UVA | 1 | |
| 15 | A and B and Compilation Errors | Codeforces | Codeforces Round #294 (Div. 2) | 1 |
| 16 | Fraction | Codeforces | Codeforces Round #433 (Div. 2, based on Olympiad of Metropolises) | 1 |
| 17 | "Accordian" Patience | UVA | 1 | |
| 18 | Web Navigation | PKU | 1 | |
| 19 | Mother bear | UVA | 1 | |
| 20 | The New Year: Meeting Friends | Codeforces | Codeforces Round #375 (Div. 2) | 1 |
| 21 | Newspaper | UVA | 1 | |
| 22 | The Bus Driver Problem | UVA | 1 | |
| 23 | Machined Surfaces | UVA | 1 | |
| 24 | Timofey and cubes | Codeforces | Codeforces Round #395 (Div. 2) | 1 |
| 25 | Sort the Array | Codeforces | Codeforces Round #258 (Div. 2) | 1 |
| 26 | Equation | UVA | 1 | |
| 27 | Unimodal Array | Codeforces | Codeforces Round #424 (Div. 2, rated, based on VK Cup Finals) | 1 |
| 28 | Sale | Codeforces | Codeforces Beta Round #34 (Div. 2) | 1 |
| 29 | Little Girl and Maximum Sum | Codeforces | Codeforces Round #169 (Div. 2) | 1 |
| 30 | Parentheses Balance | UVA | 1 | |
| 31 | Keyboard Layouts | Codeforces | Codeforces Round #424 (Div. 2, rated, based on VK Cup Finals) | 1 |
| 32 | Vanya and Lanterns | Codeforces | Codeforces Round #280 (Div. 2) | 1 |
| 33 | Replacement | Codeforces | Codeforces Round #316 (Div. 2) | 2 |
| 34 | Is it rated? | Codeforces | Codeforces Round #412 (rated, Div. 2, base on VK Cup 2017 Round 3) | 2 |
| 35 | DONALDO | SPOJ | 2 | |
| 36 | Ada and Queue | SPOJ | 2 | |
| 37 | Chess Tourney | Codeforces | Educational Codeforces Round 27 | 2 |
| 38 | Containers | UVA | 2 | |
| 39 | Borrowers | UVA | 2 | |
| 40 | Grid Successors | UVA | 2 | |
| 41 | Alternating Current | Codeforces | Codeforces Round #200 (Div. 1) & Codeforces Round #200 (Div. 2) | 2 |
| 42 | Musical Loop | UVA | 2 | |
| 43 | Chat Order | Codeforces | VK Cup 2016 - Qualification Round 1 | 2 |
| 44 | Bear and Prime Numbers | Codeforces | Codeforces Round #226 (Div. 2) | 3 |
| 45 | Time Jumper (Easy) | A2 Online Judge | 3 | |
| 46 | Pole Position | UVA | 3 | |
| 47 | z-sort | Codeforces | Educational Codeforces Round 10 | 3 |
| 48 | Unique Factorization | UVA | 3 | |
| 49 | Synching Signals | UVA | 3 | |
| 50 | Formula 1 | UVA | 3 | |
| 51 | Longest Regular Bracket Sequence | Codeforces | Codeforces Beta Round #5 | 3 |
| 52 | Minimal string | Codeforces | Educational Codeforces Round 19 | 4 |
| 53 | Fruits | Codeforces | Codeforces Beta Round #12 (Div 2 Only) | 4 |
| 54 | The Smallest String Concatenation | Codeforces | Educational Codeforces Round 9 | 4 |
| 55 | Brothers | UVA | 4 | |
| 56 | Maximum Xor Secondary | Codeforces | Codeforces Round #172 (Div. 1) & Codeforces Round #172 (Div. 2) | 5 |