package normal;

import java.util.Stack;

/**
 * @program JavaBooks
 * @description: 155.最小栈
 * @author: mf
 * @create: 2019/11/07 12:01
 */

/*
题目：https://leetcode-cn.com/problems/min-stack/
类型：栈
难度：easy
 */

/*
MinStack minStack = new MinStack();
minStack.push(-2);
minStack.push(0);
minStack.push(-3);
minStack.getMin();   --> 返回 -3.
minStack.pop();
minStack.top();      --> 返回 0.
minStack.getMin();   --> 返回 -2.
 */
public class MinStack {
    private int min = Integer.MAX_VALUE;
    private Stack<Integer> stack;
    public static void main(String[] args) {
        MinStack minStack = new MinStack();
        minStack.push(-2);
        minStack.push(0);
        minStack.push(-3);
        System.out.println(minStack.getMin());
        minStack.pop();
        System.out.println(minStack.getMin());
    }

    public MinStack() {
        stack = new Stack<>();
    }

    public void push(int x) {
        if (min >= x) {
            stack.push(min);
            min = x;
        }
        stack.push(x);
    }

    public void pop() {
        if (stack.pop() == min) {
            min = stack.pop();
        }
    }

    public int top() {
        return stack.peek();
    }

    public int getMin() {
        return min;
    }

}