java排序算法-选择排序
public class SelectionSort { private static void selectSortTest() { int[] sortArray = { 5, 2, 4, 1, 3 }; System.out.print("选择排序前: "); Utils.printArray(sortArray); selectSort(sortArray); System.out.print("选择排序后: "); Utils.printArray(sortArray); } public static void selectSort(int[] sort) { int temp; for (int i = 0; i < sort.length - 1; i++) { for (int j = i + 1; j < sort.length; j++) { if (sort[i] > sort[j]) { temp = sort[i]; sort[i] = sort[j]; sort[j] = temp; } } } } public static void heapSortTest(){ int[] arr = { 5, 2, 4, 1, 3 }; Utils.printArray("堆排序前:",arr); heapSort(arr); Utils.printArray("堆排序后:",arr); } public static void heapSort(int[] arr) { int arrLen = arr.length; int temp = 0; //建立堆 for (int i = (arrLen-1) / 2; i >= 0; i--) adjustHeap(arr, i, arrLen); //调整堆 for (int i = arrLen - 2; i >= 0; i--) { temp = arr[i + 1]; arr[i + 1] = arr[0]; arr[0] = temp; adjustHeap(arr, 0, i + 1); // Utils.printArray("第"+(9-i)+"次调整:",arr); } } public static void adjustHeap(int[] arr, int ri, int n) { int temp = arr[ri]; int ci = 2 * ri + 1; while (ci <= n - 1) { if (ci < n - 1 && arr[ci] < arr[ci + 1]) ci++; if (temp >= arr[ci]) break; arr[(ci - 1) / 2] = arr[ci]; ci = 2 * ci + 1; } arr[(ci - 1) / 2] = temp; } public static void main(String [] args){ selectSortTest(); heapSortTest(); } }