7. 理论讲解：堆栈、队列（Stack、Queue）

1. Stack - First In First Out (FIFO)
   • Array or Linked List
2. Queue - First In Last Out (FILO)
   • Array or Linked List

1. Stack

入栈与出栈

2. Queue

练习题目

1. https://leetcode.com/problems/backspace-string-compare/description/
2. https://leetcode.com/problems/implement-queue-using-stacks/solution/
3. https://leetcode.com/problems/implement-stack-using-queues/description/
4. https://leetcode.com/problems/valid-parentheses/description/