Question

好的，我再次请求你们的帮助。

我有一个正常的队列实现。但我还想在代码中添加一个方法，该方法将读取用户手动输入的数字数组。然后检查每个项目是否是素数。如果找到素数，那么它应该输出它。我尝试了一些东西，但它没有输出任何可取的东西。

我尝试找到有关它的信息，但没有成功。

这是我的代码：

Que Class：

class Que{
private int size;
private int front = -1;
private int rear = -1;
private Integer[] queArr;

public Que(int size) { //Definition of the structure size.
    this.size = size;
    queArr = new Integer[size];
}
public void insert(int item) {
    if(rear == size-1) {     // case if the structure is full
        System.out.println("queue is overflowing");
    }
    else if(front==-1) {
        rear++;
        queArr[rear] = item;
        front = rear;
    }
    else {
        rear++;
        queArr[rear] = item;
    }
}
public void delete() {
    if(front == -1) { //case if the structure is empty.
        System.out.println("queue is underflow");
    }
    else if(front==rear) {  //case to delete the first item in the queue
        System.out.println("removing "+queArr[front]);
        queArr[front] = null;
        front--;
        rear--;
    }
    else {
        System.out.println("removing "+queArr[front]);
            queArr[front] = null;

        for(int i=front+1;i<=rear;i++) {
            queArr[i-1]=queArr[i];
        }
        rear--;
    }
}
public void display() {
    if(front==-1)
        System.out.println("queue is empty");
    else
    {
        System.out.println("queue is:");
        for(int i=front;i<=rear;i++) {
            System.out.print(queArr[i]+"\t");
        }
    }
}
public void task(){

     //loop through the numbers one by one
    for (int n = front; n<=rear; n++) {
        boolean prime = true;
        //analyzes if n is prime

        for (int j = 2; j < n; j++) {
            if (n % j == 0 ) {
                prime = false;
                break; // exit the inner for loop
            }
        }

        //outputs primes
        if (prime && n != 1) {
            System.out.print(n + " ");
        }
    }
}
}

和Run类：

import java.util.Random;

import java.util.Scanner;

public class Run {

public static void main(String[] args) {

    System.out.println("Queue.");
    Scanner scan = new Scanner(System.in);
    System.out.println("How much space is needed?");

    int size = scan.nextInt();

    Que que = new Que(size);

    char ch;

    do{

        System.out.println("\nOptions \n");
        System.out.println("1. Insert a new item.");
        System.out.println("2. delete an item from the list.");
        System.out.println("3. Randomly insert an item in the list.");
        //System.out.println("4. task");

        int choice = scan.nextInt();

        switch(choice) {
            case 1: System.out.println("Enter a number!");
                que.insert(scan.nextInt());
                break;

            case 2:que.delete();
                break;

            case 3:  Random rand = new Random();
                que.insert(rand.nextInt(size));
                break;
            case 4: que.task();
        }
        que.display();
        System.out.println("\nDo you want to continue (Type y or n) \n");
        ch = scan.next().charAt(0);
    }
    while(!(ch=='N' || ch=='n'));
}

}

任何想法或指示？

Java：从任何数字的数组中读取素数并显示它们

0 个答案: