publicstatic int[]qsort(int arr[],int start,int end){
int pivot = arr[start];
int i = start;
int j = end;while(i<j){//注意必须是先从右边找//左大又小的话,就继续移动,while((i<j)&&(arr[j]>pivot)){
j--;}while((i<j)&&(arr[i]<pivot)){
i++;}//大小交换,不用分步做了if((arr[i]==arr[j])&&(i<j)){
i++;}else{
int temp = arr[i];
arr[i]= arr[j];
arr[j]= temp;}}//递归实现,分治的想法if(i-1>start) arr=qsort(arr,start,i-1);if(j+1<end) arr=qsort(arr,j+1,end);return(arr);}publicstaticvoidmain(String[] args){
int arr[]=newint[]{3,4,3,7,9,23,7};
int len = arr.length-1;
arr=qsort(arr,0,len);for(int i:arr){
System.out.print(i+"\t");}}