KwickClips Java · 44 sec · free
Which plate comes off a pile first?
Short answer. The top one, the last one added. That is LIFO.
What does peek do?
It shows the top item without removing it.
Stack: LIFO
| Operation | Stack | Gives |
|---|---|---|
| push(10) | 10 | - |
| push(20) | 10, 20 | - |
| peek() | 10, 20 | 20 |
| pop() | 10 | 20 |
Remember
| LIFO: last in, first out |
| push adds, pop removes |
| peek only looks |
A pile of plates. Which one do you take first? The top one. Push ten. Push twenty on top. Peek shows twenty. Pop removes twenty. Remember. A stack is last in, first out. Push adds and pop removes. Peek only looks.
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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