快排写法

     private static void qsort_asc(int source[],int low,int high)
     {
         if(low<high)
         {
             int i=low;
             int j=high;
             int x=source[i];
             while(i<j)
             {
                 while(i<j&&x<source[j])
                     j--;
                 if(i<j)
                 {
                     source[i]=source[j];
                 }
                 while(i<j&&x>source[i])
                     i++;
                 if(i<j)
                     source[j]=source[i];
             }
             source[i]=x;
             qsort_asc(source,low,i-1);
             qsort_asc(source,i+1,high);
         }
     }

一个函数搞定

 private static int partion(int source[],int low,int high)
     {
         int x=source[low];
         if(low<high)
         {
             while(low<high)
             {
                 while(low<high&&x<source[high])
                     high--;
                 if(low<high)
                 {
                     source[low]=source[high];
                 }
                 while(low<high&&x>source[low])
                     low++;
                 if(low<high)
                     source[high]=source[low];
             }
             source[low]=x;
         }
         return low;
     }
     private static void QSort(int source[],int low,int high)
     {
         if(low<high)
         {
             int pivotpost=partion(source,low,high);
             QSort(source,low,pivotpost-1);
             QSort(source,pivotpost+1,high);
         }
     }