Backend Engineering, Frontend Engineering
Senior
programming
When would you use the second argument in useEffect?
A) To specify dependencies that will trigger the effect on change.
B) To run the effect only once on mount.
C) To prevent infinite loops.
D) All of the above.
```
## Approach
The second argument in useEffect is crucial for optimizing performance by controlling when the effect runs in relation to the dependencies specified. It helps in preventing unnecessary renders or infinite loops.
## Complexity
**Time:** O(...) (depends on the effect's complexity)
**Space:** O(...) (depends on dependencies in effect)
## Trade-offs
- Well-managed dependencies can lead to improved performance but may require careful consideration.
```
Trusted by 100+ professionals preparing for interviews
Trusted by 100+ professionals
50+ Company Question Banks
5+ Supported Languages
Practice More Questions Like This
Generate unlimited interview questions with structured answers, code runner, and AI-powered walkthroughs.
Get Started Free
More Backend Engineering, Frontend Engineering Interview Prep
In React, what is the purpose of the useEffect hook?
Backend Engineering, Frontend Engineering · Senior
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.