> For the complete documentation index, see [llms.txt](https://maksimdan.gitbook.io/interview-practice-problems/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard.md).

# Hard

- [Add Without Plus](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/add-without-plus.md)
- [Shuffle](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/shuffle.md)
- [Random Set](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/random-set.md)
- [Count of 25](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/count-of-25.md)
- [Baby Names](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/baby-names.md)
- [Majority Element](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/majority-element.md)
- [Word Distance](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/word-distance.md)
- [The Masseuse](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/the-masseuse.md)
- [Word Transformer](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/word-transformer.md)
- [Sparse Similarity](https://maksimdan.gitbook.io/interview-practice-problems/coding_practice_questions/hard/sparse-similarity.md)