20162316刘诚昊 2017-2018-2 《Java程序设计》课下排序测试

实验要求

1 给定下列数据：90 8 7 56 123 235 9 1 653
用JDB或IDEA单步跟踪下列算法的执行过程：选择排序，插入排序，希尔排序，冒泡排序，快速排序，归并排序
2 提交每一趟的截图，要全屏，包含自己的学号信息
3 课下把代码推送到代码托管平台

过程：

1.载入书上的代码“Sorting”：

public class Sorting {//----------------------------------------------------------------------------// Sorts the specified array of integers using the selection// sort algorithm//----------------------------------------------------------------------------public static void selectionSort(Comparable[] data) {int min;for (int index = 0; index < data.length - 1; index++) {min = index;for (int scan = index + 1; scan < data.length; scan++)if (data[scan].compareTo(data[min]) < 0)min = scan;swap(data, min, index);}}//----------------------------------------------------------------------------//  Swaps two elements in the specified array//----------------------------------------------------------------------------private static void swap(Comparable[] data, int index1, int index2) {Comparable temp = data[index1];data[index1] = data[index2];data[index2] = temp;}//----------------------------------------------------------------------------// Sorts the specified array of object using an insertion// sorts algorithm//-----------------------------------------------------------------------------public static void insertionSort(Comparable[] data) {for (int index = 1; index < data.length; index++) {Comparable key = data[index];int position = index;// Shift larger values to the rightwhile (position > 0 && data[position - 1].compareTo(key) > 0) {data[position] = data[position - 1];position--;}data[position] = key;}}//-----------------------------------------------------------------------------// Sorts the specified array of objects using a bubble sort// algorithm.//------------------------------------------------------------------------------public static void bubbleSort(Comparable[] data) {int position, scan;for (position = data.length - 1; position >= 0; position--) {for (scan = 0; scan <= position - 1; scan++)if (data[scan].compareTo(data[scan + 1]) > 0)swap(data, scan, scan + 1);}}//--------------------------------------------------------------------------------// Sorts the specified array of objects using the quick sort algorithm.//--------------------------------------------------------------------------------public static void quickSort(Comparable[] data, int min, int max){int pivot;if (min < max){pivot = partition (data, min, max); //make partitionsquickSort(data, min, pivot-1); //sort left partitionquickSort(data, pivot+1, max);}}//----------------------------------------------------------------------------------// Creates the partitions needed fof quick sort.//-----------------------------------------------------------------------------------private static int partition(Comparable[] data, int min, int max){//Use first element as the partiton value.Comparable partitionValue = data[min];int left = min;int right = max;while (left < right){// Search for an element that is > the partition elementwhile (data[left].compareTo(partitionValue) <= 0 && left < right)left++;// Search for an element that is < the partition elementwhile (data[right].compareTo(partitionValue) >0)right--;if (left < right)swap(data, left, right);}// Move the partition element to its fianl positionswap(data, min, right);return right;}//------------------------------------------------------------------------------------// Sorts the speceified array of objects using the merge sort algorithm//-------------------------------------------------------------------------------------public static void mergeSort(Comparable[] data, int min, int max){if (min < max){int mid = (min + max) / 2;mergeSort(data, min, mid);mergeSort(data, mid+1, max);merge (data, min, mid, max);}}//------------------------------------------------------------------------------------// Sorts the specified array of objects using the merge sort algorithm.//-------------------------------------------------------------------------------------public static void merge(Comparable[] data, int first, int mid, int last){Comparable[] temp = new Comparable[data.length];int first1 = first, last1 = mid; // endpoints of first subarrayint first2 = mid+1, last2 = last; // endpoints of second subarrayint index = first1; // next index open in temp array// Copy smaller item from each subarray intp temp until one// of the subarray is exhaustedwhile (first1 <= last1 && first2 <= last2){if (data[first1].compareTo(data[first2]) < 0){temp[index] = data[first1];first1++;}else{temp[index] = data[first2];first2++;}index++;}// Copy remaining elements from first subarray, if anywhile (first1 <= last1){temp[index] = data[first1];first1++;index++;}// Copy remaining elements from second subarray, if anywhile (first2 <= last2){temp[index] = data[first2];first2++;index++;}// Copy merged data into original arrayfor (index = first; index <= last; index++){data[index] = temp[index];}}//---------------------------------------------------------------------------------public void hillSort(Comparable[] data){int n = data.length;for (int space = n/2; space > 0; space = space /2){for (int i = 0; i < space; i++){hill(data, i, space);}}}public  void hill(Comparable[] data, int index, int space){for (int i = index + space; i < data.length; i += space){Comparable obj =  data[i];for (int j = i; j > index; j -= space){if (obj.compareTo(data[j]) < 0)data[j + space] = data[j];data[j] = obj;}}}}

2.写实现代码，并验证是否处理正确:

public class Sorting_several {public static void main(String[] args) {Sorting q = new Sorting();Comparable[] num1 = {90, 8, 7, 56, 123, 235, 9, 1, 653, 2016};q.selectionSort(num1);System.out.println("选择排序结果：");for(Comparable element : num1){System.out.print(element + " ");}System.out.println();Comparable[] num2 = {90, 8, 7, 56, 123, 235, 9, 1, 653, 2016};q.insertionSort(num2);System.out.println("插入排序结果：");for(Comparable element : num2) {System.out.print(element + " ");}System.out.println();Comparable[] num3 = {90, 8, 7, 56, 123, 235, 9, 1, 653, 2016};q.bubbleSort(num3);System.out.println("冒泡排序结果：");for(Comparable element : num3){System.out.print(element + " ");}System.out.println();Comparable[] num4 = {90, 8, 7, 56, 123, 235, 9, 1, 653, 2016};System.out.println("快速排序结果：");q.quickSort(num4,0,num4.length-1);for(Comparable element : num4){System.out.print(element + " ");}System.out.println();Comparable[] num5 = {90, 8, 7, 56, 123, 235, 9, 1, 653, 2016};System.out.println("归并排序结果：");q.mergeSort(num5,0,num5.length-1);for(Comparable element : num5){System.out.print(element + " ");}System.out.println();}
}

3.Debug 单步跟踪：
选择排序：

插入排序：

冒泡排序：

快速排序：

归并排序：