| Problem Name | Online Judge | Year | Contest | Difficulty Level | |
|---|---|---|---|---|---|
| 1 | XOR Sum | Live Archive | 2009 | Asia - Amritapuri | 1 |
| 2 | Phone List | SPOJ | 1 | ||
| 3 | Chocolate | SPOJ | 1 | ||
| 4 | Search in the dictionary! | SPOJ | 1 | ||
| 5 | Phone List | UVA | 1 | ||
| 6 | Distinct Substrings | SPOJ | 1 | ||
| 7 | Order statistic set | SPOJ | 1 | ||
| 8 | Multiple Morse Matches | Live Archive | 2001 | Europe - Central & Europe - Southwestern | 2 |
| 9 | SubXor | SPOJ | 2 | ||
| 10 | Decoding Morse Sequences | SPOJ | 2 | ||
| 11 | Phone List | TJU | 2 | ||
| 12 | Diccionário Portuñol | Live Archive | 2011 | Latin America | 2 |
| 13 | Chuỗi từ | SPOJ Vietnam | 2 | ||
| 14 | Hyper Prefix Sets | UVA | 3 | ||
| 15 | Watto and Mechanism | Codeforces | Codeforces Round #291 (Div. 2) | 3 | |
| 16 | Vasiliy's Multiset | Codeforces | Codeforces Round #367 (Div. 2) | 3 | |
| 17 | Perfect Rhyme | SPOJ | 3 | ||
| 18 | Designing T-Shirts | SPOJ | 3 | ||
| 19 | Polo the Penguin and the Tree | CodeChef | 3 | ||
| 20 | Good Substrings | Codeforces | Codeforces Round #166 (Div. 2) | 3 | |
| 21 | Tin mật | SPOJ Vietnam | 3 | ||
| 22 | Xor Queries | CodeChef | 3 | ||
| 23 | Perfect Security | Codeforces | VK Cup 2018 - Round 1 | 4 | |
| 24 | Matrix Matcher | UVA | 4 | ||
| 25 | Frequent Substrings | UVA | 4 | ||
| 26 | Sevenk Love Oimaster | SPOJ | 4 | ||
| 27 | Shortest Names | UVA | 4 | ||
| 28 | Secret Message | TJU | 4 | ||
| 29 | Cellphone Typing | UVA | 4 | ||
| 30 | Polycarp's phone book | Codeforces | ?????????? 2018 - ?????????? ????? 1 | 4 | |
| 31 | A Lot of Games | Codeforces | Codeforces Round #260 (Div. 1) & Codeforces Round #260 (Div. 2) | 4 | |
| 32 | XOR Minimization | CodeChef | 4 | ||
| 33 | Message Coding | CodeChef | 5 | ||
| 34 | Subarray Xor | CodeChef | 5 | ||
| 35 | Sausage Maximization | Codeforces | Codeforces Round #173 (Div. 2) | 5 | |
| 36 | Vitya and Strange Lesson | Codeforces | Codeforces Round #430 (Div. 2) | 5 | |
| 37 | Multiple Morse Matches | UVA | 6 | ||
| 38 | Tree | A2 Online Judge | 7 | ||
| 39 | Old Berland Language | Codeforces | Codeforces Beta Round #37 | 7 | |
| 40 | Beautiful Subarrays | Codeforces | Educational Codeforces Round 12 | 7 | |
| 41 | Kuro and GCD and XOR and SUM | Codeforces | Codeforces Round #482 (Div. 2) | 7 | |
| 42 | Xor-MST | Codeforces | Educational Codeforces Round 32 | 8 |