midStacks
Sort a Stack using Recursion.
Updated Apr 28, 2026
Short answer
Pop top, recursively sort remaining, then insert top in the correct position.
Deep explanation
Intermediate stack problems often involve monotonic properties or expression conversion. Pop top, recursively sort remaining, then insert top in the correct position.
Real-world example
Compiler syntax checking for code blocks.
Common mistakes
- Using a single variable for min-tracking instead of a stack (fails when min is popped).
Follow-up questions
- Time complexity of sorting a stack?