Product
Pricing
Blog
Forum
NEW
Referral
Description
Solution
Discussion
Submissions
Ask AI
AI Insights
Quick Summary
Generate all valid letter combinations from a digit string using a custom phone keypad mapping.
Consecutive identical digits can be grouped, where the group size selects the corresponding letter from the mapping.
Systematically explore all valid groupings and letter selections using recursion.
What This Tests
Recursive backtracking and decision tree exploration
String partitioning and dynamic index tracking
Constraint validation during state transitions
Combinatorial generation techniques
Common Patterns
Backtracking
Collapse
Hint 1
Hint 2
What Interviewers May Ask Next
Report
Report seen similar question in interview
Accepted
1.5k
/2.7k
Acceptance Rate
54.2%
Ask AI Assistant
Ask AI Assistant
Ask me anything about this coding question!
Python3
Auto
Debug
Run
Submit
Test Cases
Input
digits =
Output
Expected
