java - 如何显示数组的元素而不是值

Question

嗨，我正在尝试创建一段代码，生成一个随机长度为 15 的数组，然后为每个元素提供一个 0-100 之间的随机数，我希望能够测试点 1 之间的距离(设置为0)并且存储在数组中的距离例如元素2的值为60，因此距点1的距离为60，我不想显示距点1的距离，而是想显示哪些点从最小到最大最接近点1，到目前为止我首先将数组排序为最小的数字，但是我想知道如何显示哪个元素存储什么距离，而不是相反，例如距离点 1(0) 最近的点是点 4(89，第二个最近的点第 1 点是第 3(25) 点，这是我到目前为止的代码:

static double distance(double x1, double x2)  
            {  
            return Math.sqrt((x2-x1)*(x2-x1) );
            //Math.sqrt is the square root of the 2 co-ordinates
            }  
public static void main(String[] args)  
{     

    Random randomGenerator = new Random();
    double x2, x1; //The Points
     x1 = 0;
    double distance;//The Math to work out distance  
    int randomInt2 = randomGenerator.nextInt(15)+1;//For Length of array  
    double [] distances = new double [randomInt2];//The Array
    double store;


    System.out.println("Distance Generated for point 1 : 0" );
    System.out.println("Amount of points created is: "+randomInt2 );

    int range = 0;//Amount of Points
    while (range < randomInt2) {  
    int randomInt3 = randomGenerator.nextInt(1000);//Distance for all points besides first     
    x2 = randomInt3;      
    distance = distance(x1,x2);      
    store = distance;//stores the distance to be put into array
    distances[range] = store;
    range++;//increments amount of points each time      
    }

    for (double val : distances) {
    System.out.print("["+val+"],");
    }

    Arrays.sort(distances);// sorts array from highest to lowest 
    System.out.println("\nThe Nearest to point 1 is: " + distances[0]);

任何帮助将不胜感激

Answer 1

Java 的 SortedMap 提供了一种按键排序的方法，同时保持与关联值的关系。

double[] distances = new double[]{ 1, 3, 2, 0.5 };
SortedMap<Double, Integer> arrayIndexByDistance = new TreeMap<>();
for (int i = 0; i < distances.length; i++) {
    arrayIndexByDistance.put(distances[i], i);
}
System.out.println("Distances (sorted): " + arrayIndexByDistance.keySet());
System.out.println("Indexes (sorted by distance): " + arrayIndexByDistance.values());

输出:

Distances (sorted): [0.5, 1.0, 2.0, 3.0]
Indexes (sorted by distance): [3, 0, 2, 1]