shell&insertion&selection.zip_排序算法

package sort; public class Shell { @SuppressWarnings("rawtypes") public static void sort(Comparable[] a) { //将a[]按升序排列 int N = a.length; //数组长度 int h = 1; while(h < N/3) h = 3*h + 1; //1,4,13,40,121,364,1093,... while(h >= 1) { //将数组变为h有序 for(int i = h; i < N; i++) { //将a[i]插入到a[i-h],a[i-2*h],a[i-3*h]...之中 for(int j = i; j >= h && less(a[j], a[j-h]); j-=h) exch(a, j, j-h); } h = h/3; } } private static boolean less(Comparable v, Comparable w) { return v.compareTo(w) < 0; } private static void exch(Comparable[] a, int i, int j) { Comparable t = a[i]; a[i] = a[j]; a[j] = t; } private static void show(Comparable[] a) { //在单行中打印数组 for(int i = 0; i < a.length; i++) System.out.print(a[i] + " "); System.out.println(); } public static boolean isSorted(Comparable[] a) { //测试数组元素是否有序 for(int i = 1; i < a.length; i++) if(less(a[i], a[i-1])) return false; return true; } public static void main(String[] args) { Comparable []a = {100,99,101,120,98,107,109,81,101,90}; sort(a); assert isSorted(a); show(a); } }