如何从its循环中重用数组的元素？

Question

我试图创建一个代码，该代码按照用户的升序在数组-by中重新排列给定的元素，我已经这样做了，但是程序需要在排序之后打印给定的元素，然后在排序之前打印它们。我对在排序后打印元素没有问题。

问题是在排序之前打印它们，如何将给定的元素由用户重新使用，以使其退出for循环。

import java.util.*;

public class SortingnumbersANDswapping {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int swap;  
        int ar[] = new int[3]; //{8,10,5}
        for (int S = 0; S < ar.length; S++) {
            ar[S] = in.nextInt();    //this for loop is used to store numbers in the array

        }
 
 
        for (int i = 0; i < ar.length; i++) {
            /* this nested for loop is used to compare the first element with the second one in the array
              or the second element with the third.
             */
            for (int j = i + 1; j < ar.length; j++) {
                if (ar[i] > ar[j]) {           //8>10-->F  ,  8>5 -->T ,     {5,10,8}  the new arrangment we are going to use
                    swap = ar[i];             // 10>8-->T               {5,8,10}
                    ar[i] = ar[j];
                    ar[j] = swap;

                }
            }

            System.out.println(ar[i]);  // to print the new order print it inside the array
            
        }
              
        // I wanna do something like that
        // System.out.println(ar[S]);
        // but of course I cant cause array S is only defined in it's loop       
    }

}

Answer 1

您不能重用它，您需要将原始数组保存在另一个保持不变的数组中。此外，在Java中，数组通常被声明为int[] ar，而不是int ar[]。以下内容应按预期的方式发挥作用：

public class SortingnumbersANDswapping {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int swap;
        int[] ar = new int[3]; //{8,10,5}
        for (int S = 0; S < ar.length; S++) {
            ar[S] = in.nextInt();    //this for loop is used to store numbers in the array
        }

        System.out.println("::: Original Array :::");
        int[] originalArray = Arrays.copyOf(ar, ar.length);
        for (int j : originalArray) {
            System.out.println(j);
        }

        System.out.println("::: Sorted Array :::");
        for (int i = 0; i < ar.length; i++) {
            for (int j = i + 1; j < ar.length; j++) {
                if (ar[i] > ar[j]) {           //8>10-->F  ,  8>5 -->T ,     {5,10,8}  the new arrangment we are going to use
                    swap = ar[i];             // 10>8-->T               {5,8,10}
                    ar[i] = ar[j];
                    ar[j] = swap;

                }
            }
            System.out.println(ar[i]);  // to print the new order print it inside the array
        }
    }
}

Answer 2

在开始更改数组之前，可以使用数组库( copyOf )中的java.util.Arrays方法复制数组。在这里您可以找到一些不同的方法-- https://www.softwaretestinghelp.com/java-copy-array/amp/

Answer 3

可以使用System.out.print(Arrays.toString(arr));打印整个数组。

public static void main(String... args) {
    int[] arr = readArray(3);
    
    System.out.print(Arrays.toString(arr));
    
    for (int i = 0; i < arr.length; i++) {
        for (int j = i + 1; j < ar.length; j++) {
            if (arr[i] > arr[j]) {
                swap(arr, i, j);
                System.out.print(Arrays.toString(arr));
            }
        }
    }
}

private static int[] readArray(int size) {
    System.out.format("Enter %d elements:\n", size);
    
    Scanner scan = new Scanner(System.in);
    int[] arr = new int[size];
    
    for(itn i = 0; i < arr.length; i++)
        arr[i] = scan.nextInt();
    
    return arr;
}

private static void swap(int[] arr, int i, int j) {
    int tmp = arr[i];
    arr[i] = arr[j];
    arr[j] = tmp;
}