Stack Practice Questions
A curated set of stack problems. These cover the patterns you’ll see again and again — bracket matching, monotonic stacks, expression evaluation, and stack design.
Try each one before peeking at the solution. The interview question isn’t usually “do you know what a stack is” — it’s “can you recognize when one would help?” These problems train that recognition.
Easy
| Problem | Pattern | Status |
|---|---|---|
| Valid Parentheses | Matching pairs | Available |
| Min Stack | Auxiliary stack | Available |
| Implement Queue using Stacks | Two stacks | Available |
Medium
| Problem | Pattern | Status |
|---|---|---|
| Next Greater Element | Monotonic stack | Available |
| Evaluate Reverse Polish Notation | Expression evaluation | Available |
| Daily Temperatures | Monotonic stack | Available |
More Practice (Coming Soon)
| Problem | Pattern | Status |
|---|---|---|
| Largest Rectangle in Histogram | Monotonic stack | Coming Soon |
| Trapping Rain Water | Monotonic stack / DP | Coming Soon |
| Asteroid Collision | Simulation + stack | Coming Soon |
| Basic Calculator | Expression eval | Coming Soon |
| Decode String | Nested structure | Coming Soon |
| Remove K Digits | Monotonic stack | Coming Soon |