155. Min Stack
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.
Implement the MinStack class:
- MinStack() initializes the stack object.
- void push(int val) pushes the element val onto the stack.
- void pop() removes the element on the top of the stack.
- int top() gets the top element of the stack.
- int getMin() retrieves the minimum element in the stack.
分别将数据保存在一个Priority Queue和一个栈中。
pop方法pop掉stack的内容,然后将其从优先队列中移除。
top方法返回stack的栈顶。
getMin方法返回优先队列的顶。
1 | class MinStack { |
155. Min Stack