添加 最大堆

Author: Jiang Haifeng

Heap/src/MaxHeap.java

@@ -0,0 +1,71 @@
+public class MaxHeap<Key extends Comparable<Key>> {
+    private Key[] data;
+    private int capacity;
+    private int count;
+
+    public int size() {
+        return count;
+    }
+
+    public boolean isEmpty() {
+        return count == 0;
+    }
+
+    public MaxHeap(int capacity) {
+        data = (Key[]) new Comparable[capacity + 1];
+        count = 0;
+        this.capacity = capacity;
+    }
+
+    private boolean less(int i, int j) {
+        return data[i].compareTo(data[j]) < 0;
+    }
+
+    private void exch(int i, int j) {
+        Key tmp = data[i];
+        data[i] = data[j];
+        data[j] = tmp;
+    }
+
+    public void swin(int k) {
+        while (k > 1 && less(k / 2, k)) {
+            exch(k / 2, k);
+            k = k / 2;
+        }
+    }
+
+    public void sink(int k) {
+        while (k * 2 <= count) {
+            int j = k * 2;
+            if (j < count && less(j, j + 1)) j++;
+            if (!less(k, j)) break;
+            exch(k, j);
+            k = j;
+        }
+    }
+
+    public void insert(Key key) {
+        data[++count] = key;
+        swin(count);
+    }
+
+    public Key delMax() {
+        Key key = data[1];
+        exch(1, count);
+        data[count--] = null;
+        sink(1);
+        return key;
+    }
+
+    public static void main(String[] args) {
+        int[] nums = {2, 3, 4, 5, 6};
+        MaxHeap<Integer> maxHeap = new MaxHeap<>(nums.length);
+        for (int i = 0; i < nums.length; i++) {
+            maxHeap.insert(nums[i]);
+        }
+        for (int i = 0; i < nums.length; i++) {
+            System.out.println(maxHeap.delMax());
+        }
+    }
+
+}

README.md

@@ -9,6 +9,8 @@
 - 【数组】
     - [静态数组](./Array/src/StaticArray.java)
     - [动态数组 ](./Array/src/Array.java) - 动态扩容
+- 【堆】
+    - [最大堆](./Heap/src/MaxHeap.java)
 - 【栈】
     - [栈](./Array/src/Array.java) - 基于[【数组】- 动态数组](./Array/src/Array.java)
 - 【队列】