算法与数据结构基础-对数器

我们在测试算法的时候不是总有完整的测试数据，但是我们大部分可以使用暴力去实现，对数器的含义在于使用相对可靠的暴力算法，使用很多次随机测试，
测试其算法输出结果是否相同，多次测试结果相同我们认为待测试算法是可靠的。

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85

package sort;   import java.util.Arrays; import java.util.Comparator;   /**  * @author rx  * @date 2022/7/25 20:14  */ public class Util{     public static int[] generateRandomArray(int maxSize, int maxValue) {         //Math.random()->[0,1)所有小数，等概率返回一个         //Math.random()*N->[0,N) 所有小数，等概率返回一个         //(int)(Math.random()*N->[0,N-1] 所有整数，等概率返回一个         //长度随机         int[] arr = new int[(int) (Math.random() * (maxSize + 1))];         for (int i = 0; i < arr.length; i++) {             arr[i] = (int) (Math.random() * (maxValue + 1)) - (int) (Math.random() * maxValue);         }         return arr;     }       public static int[] copyArray(int[] arr) {         if (arr == null) {             return null;         }         int[] res = new int[arr.length];         for (int i = 0; i < arr.length; i++) {             res[i] = arr[i];         }         return res;     }       //选择排序     public static void insertionSort(int[] arr) {         for (int i = 0; i < arr.length; i++) {             int minIndex = i;             for (int j = i; j < arr.length; j++) {                 minIndex = arr[minIndex] > arr[j] ? j : minIndex;             }             swap(arr, minIndex, i);         }     }       public static boolean isEqual(int[] arr1, int[] arr2) {         int len = arr1.length;         for (int i = 0; i < len; i++) {             if (arr1[i] != arr2[i]) {                 return false;             }         }         return true;     }       public static void swap(int[] arr, int i, int j) {         int temp = arr[i];         arr[i] = arr[j];         arr[j] = temp;     }       public static void comparator(int[] arr) {         Arrays.sort(arr);     }       public static void main(String[] args) {           int testTime = 500000;         int maxSize = 100;         int maxValue = 100;         boolean success = true;         for (int i = 0; i < testTime; i++) {             int[] arr1 = generateRandomArray(maxSize, maxValue);             int[] arr2 = copyArray(arr1);             insertionSort(arr1);             comparator(arr2);             if (!isEqual(arr1, arr2)) {                 success = false;                 break;             }         }         System.out.println(success ? "Nice" : "defeat");         } }