[Java知识库]Java实现栈

1. 利用顺序表实现，即使用尾插 + 尾删的方式实现

2. 利用链表实现，则头尾皆可 相对来说，顺序表的实现上要更为简单一些，所以我们优先用顺序表实现栈

package stack;

public class Test {
    public static void main(String[] args) {
        myStack1 m = new myStack1();
        m.push(1);
        m.push(2);
        m.push(3);
        m.push(4);
        m.push(5);
        m.push(6);
        System.out.println(m.pop());
        System.out.println(m.peek());
        myStack2 m2=new myStack2();
        m2.push(7);
        m2.push(8);
        m2.push(8);
        m2.push(9);
        System.out.println(m2.pop());
        System.out.println(m2.peek());
        System.out.println(m2.peek());


    }
}

//数组实现栈
class myStack1 {
    private int[] elem = new int[2];
    private int size = 0;

    //压栈
    public void push(int e) {
        if (isFull()) {
            this.elem = expend(elem);
        }
        elem[size] = e;
        size++;
    }

    //出栈
    public int pop() {
        return elem[--size];
    }

    //查看栈顶元素
    public int peek() {
        return elem[size - 1];
    }

    //判断是否满了
    public boolean isFull() {
        if (size == elem.length) {
            return true;
        }
        return false;
    }

    public int[] expend(int[] e) {
        int[] newElem = new int[e.length * 2];
        return newElem;
    }
}

//链表实现栈
class myStack2 {
    private int data;
    private myStack2 next;
    public myStack2(){

    }
    public myStack2(int data) {
        this.data = data;
    }

    public myStack2 head;

    //压栈
    public void push(int data) {
        myStack2 m = new myStack2(data);
        if (this.head == null) {
            this.head = m;
        }
        m.next=this.head;
        this.head=m;

    }
    //出栈
    public int pop(){
        int ret=this.head.data;
        this.head=this.head.next;
        return ret;
    }
    //产看栈顶元素
    public int peek(){
        return this.head.data;
    }
}

整个思路不是很严谨，只能呈献出比较简单的栈。