Подскажите,как врубиться в суть решения задачи

class HeapQuiz {
   int id = 0;
public statiс void main(String [] args) {
   int x = 0;
HeapQuiz [] hq = new HeapQuiz[5];
   while (x < 3) {
hq[x] = new HeapQuiz();
hq[x].id = x;
x = x + 1;
}
hq[3] = hq[1];
hq[4] = hq[1];
hq[3] = null;
hq[4] = hq[0];
hq[0] = hq[3];
hq[3] = hq[2];
hq[2] = hq[0];

public class HeapQuiz {
 
    int id = 0;
 
    public static void main(String[] args) {
        int x = 0;
        HeapQuiz[] hq = new HeapQuiz[5];
        while (x < 3) {
            hq[x] = new HeapQuiz();
            hq[x].id = x;
            x = x + 1;
        }
        hq[3] = hq[1];
        hq[4] = hq[1];
        hq[3] = null;
        hq[4] = hq[0];
        hq[0] = hq[3];
        hq[3] = hq[2];
        hq[2] = hq[0];
 
        for (HeapQuiz h: hq) System.out.println(h);
 
    }
}