Find the Nearest Target Character and Support Streaming Updates
Company: Snowflake
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Technical Screen
Given an array of characters and a target character, return the distance from each index to the nearest target occurrence, or `-1` if the target never appears. Also support a streaming version that returns the newest index distance to the nearest target seen so far after each append.
Implement:
```python
def nearest_target_distances(chars: list[str], target: str) -> list[int]:
pass
def streaming_nearest_target(chars: list[str], target: str) -> list[int]:
pass
```
Quick Answer: Practice a Snowflake coding interview problem focused on find the nearest target character and support streaming updates. The prompt emphasizes edge cases, clean implementation, and verifiable test behavior without revealing the solution.
Return distance from each character to the nearest occurrence of a target character.
Examples
Input: {"chars":["a","b","c","b"],"target":"b"}
Expected Output: [1,0,1,0]
Explanation: Targets on both sides.
Input: {"chars":[],"target":"x"}
Expected Output: []
Explanation: Empty.