快速排序之java实现

             1
            
                public
                class
                 QuickSort {

                 2
                    @Test

                 3
                public
                void
                 sort(){

                 4
                int[] a = { 5, 8, 6, 2, 7, 9, 1, 7, 3 };
 5//int[] a = {3, 1, 2, 5, 7, 9, 6, 4, 8}; 6 7         sort(a, 0, a.length-1); 8        System.out.println(Arrays.toString(a));
 9    }
1011privatevoid sort(int[] a, int start, int end) {
12int i=start;
13int j=end;
14int key = a[i];
15int tmp;
16while (j > i) {//向左遍历17while (j > i && a[j] >=key)
18                 j--;
19if (a[j] < key) {
20                 tmp = a[j];  //key存在了a[j]中21                 a[j] = a[i];
22                 a[i] = tmp;
23            }
24while (j > i && a[i] <= key)
25                 i++;
26if (a[i] > key) {
27                 tmp = a[i];
28                 a[i] = a[j];
29                 a[j] = tmp;
30            }
31        }
32if(j<end)sort(a,j+1,end);
33if(i>start)sort(a,start,i-1);
34    }
3536 }