From cfd2323962ff2d1cadf523c55f67a951cde7d317 Mon Sep 17 00:00:00 2001 From: guide Date: Fri, 10 Jun 2022 17:45:13 +0800 Subject: [PATCH] Update 10-classical-sorting-algorithms.md --- .../10-classical-sorting-algorithms.md | 98 +++++++------------ 1 file changed, 35 insertions(+), 63 deletions(-) diff --git a/docs/cs-basics/algorithms/10-classical-sorting-algorithms.md b/docs/cs-basics/algorithms/10-classical-sorting-algorithms.md index 4ab00d96..81bd68a5 100644 --- a/docs/cs-basics/algorithms/10-classical-sorting-algorithms.md +++ b/docs/cs-basics/algorithms/10-classical-sorting-algorithms.md @@ -77,7 +77,7 @@ tag: * @param arr * @return arr */ -public static int[] BubbleSort(int[] arr) { +public static int[] bubbleSort(int[] arr) { for (int i = 1; i < arr.length; i++) { // Set a flag, if true, that means the loop has not been swapped, // that is, the sequence has been ordered, the sorting has been completed. @@ -130,7 +130,7 @@ public static int[] BubbleSort(int[] arr) { * @param arr * @return arr */ -public static int[] SelectionSort(int[] arr) { +public static int[] selectionSort(int[] arr) { for (int i = 0; i < arr.length - 1; i++) { int minIndex = i; for (int j = i + 1; j < arr.length; j++) { @@ -184,7 +184,7 @@ public static int[] SelectionSort(int[] arr) { * @param arr * @return arr */ -public static int[] InsertionSort(int[] arr) { +public static int[] insertionSort(int[] arr) { for (int i = 1; i < arr.length; i++) { int preIndex = i - 1; int current = arr[i]; @@ -234,7 +234,7 @@ public static int[] InsertionSort(int[] arr) { * @param arr * @return arr */ -public static int[] ShellSort(int[] arr) { +public static int[] shellSort(int[] arr) { int n = arr.length; int gap = n / 2; while (gap > 0) { @@ -291,14 +291,14 @@ public static int[] ShellSort(int[] arr) { * @param arr * @return arr */ -public static int[] MergeSort(int[] arr) { +public static int[] mergeSort(int[] arr) { if (arr.length <= 1) { return arr; } int middle = arr.length / 2; int[] arr_1 = Arrays.copyOfRange(arr, 0, middle); int[] arr_2 = Arrays.copyOfRange(arr, middle, arr.length); - return Merge(MergeSort(arr_1), MergeSort(arr_2)); + return merge(mergeSort(arr_1), mergeSort(arr_2)); } /** @@ -308,7 +308,7 @@ public static int[] MergeSort(int[] arr) { * @param arr_2 * @return sorted_arr */ -public static int[] Merge(int[] arr_1, int[] arr_2) { +public static int[] merge(int[] arr_1, int[] arr_2) { int[] sorted_arr = new int[arr_1.length + arr_2.length]; int idx = 0, idx_1 = 0, idx_2 = 0; while (idx_1 < arr_1.length && idx_2 < arr_2.length) { @@ -364,58 +364,32 @@ public static int[] Merge(int[] arr_1, int[] arr_2) { ### 代码实现 +> 来源：[使用 Java 实现快速排序（详解）](https://segmentfault.com/a/1190000040022056) + ```java -/** - * Swap the two elements of an array - * @param array - * @param i - * @param j - */ -private static void swap(int[] arr, int i, int j) { - int tmp = arr[i]; - arr[i] = arr[j]; - arr[j] = tmp; -} - -/** - * Partition function - * @param arr - * @param left - * @param right - * @return small_idx - */ -private static int Partition(int[] arr, int left, int right) { - if (left == right) { - return left; - } - // random pivot - int pivot = (int) (left + Math.random() * (right - left + 1)); - swap(arr, pivot, right); - int small_idx = left; - for (int i = small_idx; i < right; i++) { - if (arr[i] < arr[right]) { - swap(arr, i, small_idx); - small_idx++; +public static int partition(int[] array, int low, int high) { + int pivot = array[high]; + int pointer = low; + for (int i = low; i < high; i++) { + if (array[i] <= pivot) { + int temp = array[i]; + array[i] = array[pointer]; + array[pointer] = temp; + pointer++; } + System.out.println(Arrays.toString(array)); } - swap(arr, small_idx, right); - return small_idx; + int temp = array[pointer]; + array[pointer] = array[high]; + array[high] = temp; + return pointer; } - -/** - * Quick sort function - * @param arr - * @param left - * @param right - * @return arr - */ -public static int[] QuickSort(int[] arr, int left, int right) { - if (left < right) { - int pivotIndex = Partition(arr, left, right); - sort(arr, left, pivotIndex - 1); - sort(arr, pivotIndex + 1, right); +public static void quickSort(int[] array, int low, int high) { + if (low < high) { + int position = partition(array, low, high); + quickSort(array, low, position - 1); + quickSort(array, position + 1, high); } - return arr; } ``` @@ -493,7 +467,7 @@ private static void heapify(int[] arr, int i) { * @param arr * @return */ -public static int[] HeapSort(int[] arr) { +public static int[] heapSort(int[] arr) { // index at the end of the heap heapLen = arr.length; // build MaxHeap @@ -561,7 +535,7 @@ private static int[] getMinAndMax(int[] arr) { * @param arr * @return */ -public static int[] CountingSort(int[] arr) { +public static int[] countingSort(int[] arr) { if (arr.length < 2) { return arr; } @@ -640,7 +614,7 @@ private static int[] getMinAndMax(List arr) { * @param arr * @return */ -public static List BucketSort(List arr, int bucket_size) { +public static List bucketSort(List arr, int bucket_size) { if (arr.size() < 2 || bucket_size == 0) { return arr; } @@ -704,7 +678,7 @@ public static List BucketSort(List arr, int bucket_size) { * @param arr * @return */ -public static int[] RadixSort(int[] arr) { +public static int[] radixSort(int[] arr) { if (arr.length < 2) { return arr; } @@ -755,8 +729,6 @@ public static int[] RadixSort(int[] arr) { ## 参考文章 -https://www.cnblogs.com/guoyaohua/p/8600214.html - -https://en.wikipedia.org/wiki/Sorting_algorithm - -https://sort.hust.cc/ +- https://www.cnblogs.com/guoyaohua/p/8600214.html +- https://en.wikipedia.org/wiki/Sorting_algorithm +- https://sort.hust.cc/