| Problem Name | Online Judge | Year | Contest | Difficulty Level | |
|---|---|---|---|---|---|
| 1 | I Love Strings!! | UVA | 1 | ||
| 2 | Word Puzzles | SPOJ | 2 | ||
| 3 | Substring Problem | SPOJ | 2 | ||
| 4 | Emoticons | SPOJ | 3 | ||
| 5 | Censored! | Timus | 4 | ||
| 6 | Substring | UVA | 4 | ||
| 7 | Lost in Space | UVA | 5 | ||
| 8 | GRE Words Revenge | Live Archive | 2013 | Asia - Chengdu | 5 |
| 9 | Lucky Common Subsequence | Codeforces | Codeforces Round #201 (Div. 1) & Codeforces Round #201 (Div. 2) | 5 | |
| 10 | Obscene Words Filter | Timus | 5 | ||
| 11 | Prefixes and suffixes | SGU | 7 | ||
| 12 | Growing Strings | UVA | 7 | ||
| 13 | Frequency of String | Codeforces | Tinkoff Internship Warmup Round 2018 and Codeforces Round #475 (Div. 1) | 8 | |
| 14 | e-Government | Codeforces | VK Cup 2012 Round 2 | 8 | |
| 15 | Duff is Mad | Codeforces | Codeforces Round #326 (Div. 1) | 10 | |
| 16 | Digits of Number Pi | Codeforces | Codeforces Round #325 (Div. 1) | 10 |