补充非递归方式堆化 #40

Original file line number	Diff line number	Diff line change
Expand Up		@@ -176,7 +176,10 @@ public class HeapSort implements IArraySort {
		}
		}

	private void heapify(int[] arr, int i, int len) {
	/**
	* 1. 递归方式堆化
	*/
	private void heapifyRecursive(int[] arr, int i, int len) {
		int left = 2 * i + 1;
		int right = 2 * i + 2;
		int largest = i;
Expand All		@@ -191,8 +194,33 @@ public class HeapSort implements IArraySort {

		if (largest != i) {
		swap(arr, i, largest);
	heapify(arr, largest, len);
	heapifyRecursive(arr, largest, len);
	}
	}

	/**
	* 2. 非递归方式堆化
	*/
	private void heapify(int[] arr, int i, int len) {
	int tmp = arr[i];

	for (int j = i * 2 + 1; j < len; j = j * 2 + 1) {
	//比较左右子结点谁更大
	if (j + 1 < len && arr[j] < arr[j + 1]) {
	j++;
	}
	//如果子节点没父节点大,跳过
	if (arr[j] <= tmp) {
	break;
	} else {
	//将子节点的值赋给父节点
	arr[i] = arr[j];
	//升级为新的父节点
	i = j;
	}
		}

	arr[i] = tmp;
		}

		private void swap(int[] arr, int i, int j) {
Expand Down

32 changes: 30 additions & 2 deletions src/java/main/HeapSort.java

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Original file line number	Diff line number	Diff line change
Expand Up		@@ -28,7 +28,10 @@ private void buildMaxHeap(int[] arr, int len) {
		}
		}

	private void heapify(int[] arr, int i, int len) {
	/**
	* 递归方式堆化
	*/
	private void heapifyRecursive(int[] arr, int i, int len) {
		int left = 2 * i + 1;
		int right = 2 * i + 2;
		int largest = i;
Expand All		@@ -43,10 +46,35 @@ private void heapify(int[] arr, int i, int len) {

		if (largest != i) {
		swap(arr, i, largest);
	heapify(arr, largest, len);
	heapifyRecursive(arr, largest, len);
		}
		}

	/**
	* 非递归方式堆化
	*/
	private void heapify(int[] arr, int i, int len) {
	int tmp = arr[i];

	for (int j = i * 2 + 1; j < len; j = j * 2 + 1) {
	//比较左右子结点谁更大
	if (j + 1 < len && arr[j] < arr[j + 1]) {
	j++;
	}
	//如果子节点没父节点大,跳过
	if (arr[j] <= tmp) {
	break;
	} else {
	//将子节点的值赋给父节点
	arr[i] = arr[j];
	//升级为新的父节点
	i = j;
	}
	}

	arr[i] = tmp;
	}

		private void swap(int[] arr, int i, int j) {
		int temp = arr[i];
		arr[i] = arr[j];
Expand Down

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