PriorityQueue

public class PriorityQueueMain {public static void main(String[] args) {int[] temp = {40, 2, 33, 26, 35, 8, 8, 26, 29, 2};PriorityQueue<Integer> priorityQueue = new PriorityQueue<>();for (int i = 0; i < temp.length; i++) {priorityQueue.offer(temp[i]);}while (!priorityQueue.isEmpty()) {System.out.format("%d ", priorityQueue.poll());}}
}

自己实现

详细原理，只是在push的时候他写错了

public class ArraySmallHeap {public static void main(String[] args) {int[] temp = {40, 2, 33, 26, 35, 8, 8, 26, 29, 2};heap = new int[temp.length];for (int j : temp) {push(j);}for (int i = 0; i < temp.length; i++) {System.out.format("%d ", pop());}}private static int[] heap;private static int size;private static void down(int k) {int t = k;int l = k << 1, r = (k << 1) + 1;if (l <= size && heap[t] > heap[l]) {t = l;}if (r <= size && heap[t] > heap[r]) {t = r;}if (t != k) {int temp = heap[k];heap[k] = heap[t];heap[t] = temp;down(t);}}private static void up(int k) {int u = k / 2;if (u >= 1 && heap[k] < heap[u]) {int temp = heap[k];heap[k] = heap[u];heap[u] = temp;up(u);}}public static void push(int v) {heap[++size] = v;up(size);}public static int pop() {int v = heap[1];heap[1] = heap[size--];down(1);return v;}
}