import java.util.LinkedList;

// 使用链表实现栈操作
public class MyStack {
    public static void main(String[] args) {
        MyStack stack = new MyStack(5);
        int[] arr = {2, 5, 7, 8, 9, 0};
        for (int n : arr) {
            NodeStack node = new NodeStack();
            node.v = n;
            stack.push(node);
        }

        System.out.println(stack.min);
        System.out.println(stack.max);

        NodeStack n1 = stack.pop();
        System.out.println("v1=" + n1.v);

        System.out.println(stack.min);
        System.out.println(stack.max);

        NodeStack n2 = stack.pop();
        System.out.println("v2=" + n2.v);
        NodeStack n3 = stack.pop();
        System.out.println("v3=" + n3.v);

        System.out.println(stack.min);
        System.out.println(stack.max);

        NodeStack n4 = stack.pop();
        System.out.println("v4=" + n4.v);

        System.out.println(stack.min);
        System.out.println(stack.max);

        NodeStack n5 = stack.pop();
        System.out.println("v5=" + n5.v);

        System.out.println(stack.min);
        System.out.println(stack.max);

        stack.pop();

        System.out.println();
    }

    public LinkedList<NodeStack> list = null;
    private int size;

    public MyStack(int size) {
        this.size = size;
        list = new LinkedList<NodeStack>();
    }

    private int min = Integer.MAX_VALUE;
    private int max = Integer.MIN_VALUE;

    public void push(NodeStack node) {
        if (this.list.size() < this.size) {
            this.list.add(0, node);
            getMaxMin(node);
        } else {
            System.out.println("stack is full");
        }
    }

    public NodeStack pop() {
        if (this.list.size() > 0) {
            NodeStack node = this.list.get(0);
            this.list.remove(0);

            if (this.list.isEmpty()) {
                min = Integer.MAX_VALUE;
                max = Integer.MIN_VALUE;
            } else if (node.v == min) {
                min = min().v;
            } else if (node.v == max) {
                max = max().v;
            }

            return node;
        } else {
            System.out.println("stack is empty");
        }
        return null;
    }

    public void getMaxMin(NodeStack node) {
        if (min > node.v) {
            min = node.v;
        }
        if (max < node.v) {
            max = node.v;
        }
    }

    public NodeStack min() {
        min = Integer.MAX_VALUE;
        NodeStack nodeMin = null;
        for (NodeStack node : this.list) {
            if (node.v < min) {
                min = node.v;
                nodeMin = node;
            }
        }
        return nodeMin;
    }

    public NodeStack max() {
        max = Integer.MIN_VALUE;
        NodeStack nodeMin = null;
        for (NodeStack node : this.list) {
            if (node.v > max) {
                max = node.v;
                nodeMin = node;
            }
        }
        return nodeMin;
    }

    public int getMin() {
        return min;
    }

    public int getMax() {
        return max;
    }

}

class NodeStack {
    public int v;
}