Fidelity Coding Interview Questions
We track 5 coding questions asked at Fidelity, tagged with the algorithms and concepts they test. The most common: String, Array, Hash Table, Counting, Matrix.
Browse all 5 Fidelity questions →Concept mix
Each question's weight is split evenly across its concepts, so the shares sum to 100%.
- String28.3%
- Array16.7%
- Hash Table11.7%
- Matrix10.0%
- Two Pointers10.0%
- Sorting6.7%
- Trie6.7%
- Counting5.0%
- Queue5.0%
How many questions involve each concept
Share of all 5 tracked Fidelity questions that touch each concept. Questions usually involve several, so these overlap.
- String80.0%
- Array40.0%
- Hash Table40.0%
- Counting20.0%
- Matrix20.0%
- Queue20.0%
- Sorting20.0%
- Trie20.0%
- Two Pointers20.0%
Where Fidelity differs from the average company
Concept weight at Fidelity relative to the average across all companies we track. Green means Fidelity leans on it harder than most.
- String3.0×
- Hash Table1.7×
Fidelity specialties
Concepts that show up at Fidelity but are rarely asked elsewhere. They are easy to get blindsided by.
Difficulty mix
Level split of the 5 tracked Fidelity questions.
- Junior100% (5)
Every concept in Fidelity interviews
| Concept | Questions | % of questions | Share of mix |
|---|---|---|---|
| String | 4 | 80.0% | 28.3% |
| Array | 2 | 40.0% | 16.7% |
| Hash Table | 2 | 40.0% | 11.7% |
| Counting | 1 | 20.0% | 5.0% |
| Matrix | 1 | 20.0% | 10.0% |
| Queue | 1 | 20.0% | 5.0% |
| Sorting | 1 | 20.0% | 6.7% |
| Trie | 1 | 20.0% | 6.7% |
| Two Pointers | 1 | 20.0% | 10.0% |
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