# stack vs queue

###### tags: `java`

| | stack | queue |
|:---------------:|:--------------------------------:|:--------------------------------------------------:|
| implement | Stack implement Vector | LinkedList,ArrayList,PriorityQueue implement Queue |
| InOut | FILO | FIFO |
| peek | peek(),throw StackEmpty if empty | peek(), return null if empty |
| remove 1st node | pop(),throw StackEmpty if empty | poll(), return null if empty |
| add | add(el) | offer(el) |