public class MyStack {
class Node {// 定义节点
private Node next;
public Object value;
}
Node top = null;
void init() {//初始话头结点
top = new Node();
top.next = null;
top.value = null;
}
public void push(Object element) {//采用头插发的方式模拟入栈
Node e = new Node();
e.value = element;
if (top.next == null) {
top.next = e;
} else {
e.next = top.next;
top.next = e;
}
}
public Object pop() {//弹出栈顶元素，也就是头结点后面的第一个元素
Object ele = null;
if (top.next == null) {
System.out.println("栈为空!");
} else {
ele = top.next.value;
top.next = top.next.next;//移动指针。相当于删除链表中第一个元素
}
return ele;
}
public Object peek()//返回栈顶元素,不执行出栈操作
{
if(top.next==null)
{
return -1;
}
else
return top.next.value;
}
public boolean isempty()//判断栈是否为空
{
return top.next==null?true:false;
}
public int size() {//返回栈的大小，含有的元素个数
Node temp = top;
int i = 0;
while (temp.next != null) {
i++;
temp = temp.next;
}
return i;
}
public void print() {//打印栈中存在的元素
Node temp = top;
if(temp.next==null)
{
System.out.println("栈为空！");
}
while (temp.next != null) {
System.out.print(temp.next.value + " ");
temp = temp.next;
}
}
public static void main(String[] args) {
MyStack stack = new MyStack();
stack.init();
for (int i = 0; i < 5; i++) {
stack.push(i);
}
/*Object ele1 = stack.pop();
Object ele2 = stack.pop();
Object ele3 = stack.pop();
Object ele4 = stack.pop();
Object ele5 = stack.pop();
System.out.println(ele1);
System.out.println(ele2);
System.out.println(ele3);
System.out.println(ele4);
System.out.println(ele5);*/
Object ele1 = stack.pop();
System.out.println("此次弹出的元素为:"+ele1);
System.out.print("栈中剩余的元素为:");
stack.print();
System.out.println();
System.out.println("栈顶元素为:"+stack.peek());
}
}
