KwickClips Java · 42 sec · free
What does top = -1 mean?
Short answer. The stack is empty.
What must a full version check?
Overflow when pushing to a full stack and underflow when popping an empty one.
Remember
| Stack: array plus top |
| Queue: front and rear |
| Check overflow, underflow |
An array and one index make a stack! Top starts at minus one. Push raises top, then stores. Pop returns, then lowers top. Remember. A stack needs an array and top. A queue needs front and rear. Always check overflow and underflow.
This clip is from the full lesson: Stacks, Queues and Deques Using Classes — 7 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: ISC Class 11 Computer Science (868), ISC Class 12 Computer Science (868), Programming All levels Java, Programming All levels Java
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