Java栈与队列的实现

前言

栈与队列的实现采用动态分配内存，保证了使用的灵活性

栈

package Stack;

import java.util.Arrays;

public class Stack {
    int length = 0;
    int[] arr;
    public Stack() {
        this.length = 0;
        arr = new int[this.length];
    }
    public Stack(int length) {
        this.length = length;
        arr = new int[this.length];
    }
    public void Push(int val) {
        this.length++;
        int[] tmp = new int[this.length];
        for (int i = 0;i <this.length - 1;i++) {
            tmp[i] = arr[i];
        }
        tmp[this.length - 1] = val;
//        System.out.println(Arrays.toString(tmp));
        arr = tmp;
    }
    public int GetLength() {
        return this.length;
    }
    public int Pop() {
        int val = this.arr[this.length - 1];
        this.length--;
        int[] tmp = new int[this.length];
        for (int i = 0;i<this.length;i++) {
            tmp[i] = arr[i];
        }
        arr = tmp;
        return val;
    }
    @Override
    public String toString() {
        return "Queue{" +
                "length=" + length +
                ", arr=" + Arrays.toString(arr) +
                '}';
    }
}

队列

package Queue;

import java.util.Arrays;

public class Queue {
    int[] arr;
    int length;

    public Queue() {
        this.length = 0;
        this.arr = new int[this.length];
    }

    public Queue(int length) {
        this.length = length;
        this.arr = new int[this.length];
    }

    public void Push(int val) {
        this.length++;
        int[] tmp = new int[this.length];
        for (int i = 0; i < this.length - 1; i++) {
            tmp[i] = arr[i];
        }
        tmp[this.length - 1] = val;
        arr = tmp;
    }

    public void LPush(int val) {
        this.length++;
        int[] tmp = new int[this.length];
        for (int i = 0; i < this.length - 1; i++) {
            tmp[i+1] = arr[i];
        }
        tmp[0] = val;
        arr = tmp;
    }

    public int Pop() {
        int val = this.arr[0];
        this.length--;
        int[] tmp = new int[this.length];
        for (int i = 0; i < this.length; i++) {
            tmp[i] = arr[i + 1];
        }
        arr = tmp;
        return val;
    }
    public int RPop() {
        int val = this.arr[this.length - 1];
        this.length--;
        int[] tmp = new int[this.length];
        for (int i = 0; i < this.length; i++) {
            tmp[i] = arr[i];
        }
        arr = tmp;
        return val;
    }

    public int GetLength() {
        return this.length;
    }

    @Override
    public String toString() {
        return "Queue{" +
                "arr=" + Arrays.toString(arr) +
                ", length=" + length +
                '}';
    }
}