a) 冒泡

public static void mp(int a[]) {   int swap = 0;   for (int i = 0; i < a.length; i++) {      for (int j = i; j < a.length; j++) {         if (a[j] > a[i]) {         swap = a[i];         a[i] = a[j];         a[j] = swap;      }   }}System.out.println(Arrays.toString(a));}

b)二分查找

public static int ef(int a[], int tag) {   int first = 0;   int end = a.length;   for (int i = 0; i < a.length; i++) {      int middle = (first + end) / 2;      if (tag == a[middle]) {         return middle;      }      if (tag > a[middle]) {         first = middle + 1;      }      if (tag < a[middle]) {         end = middle - 1;      }   }return 0;}