快排

package com.algorithm;


public class Sort {
public static void main(String []args){
int []a={4,4,5,7,1,8,3,9,11,6};
qsort(a,0,a.length-1);
for(int i=0;i<a.length;i++)
System.out.println(a[i]);
}


private static void qsort(int[] a, int i, int j) {
// TODO 自动生成的方法存根
int mid=0;
if(i<j){
            //递归地找分割点，排左边，排右边
mid=findP(a,i,j);
qsort(a,i,mid-1);
qsort(a,mid+1,j);
}
}
private static int findP(int[] a, int i, int j){
int m=a[i];
while(i<j){
while(i<j&&a[j]>m)j--;
a[i]=a[j];


while(i<j&&a[i]<=m)i++;
a[j]=a[i];
}
a[i]=m;
return i;
}
}