搜索引擎如何发现平面链接？(How are flat links discovered by a search engine?)

 如果在TryJava8中运行程序，我会得到正确排序的数组。 我想你可能打印输入（ fruits ），而不是输出（ arrayFruits ）。 这就是说，你打开了一个有趣的话题，因为一般来说，你是正确的排序算法并不能保证完整的秩序。 一般来说，对于大型数组，如果两个元素是等价的，但不相同（例如指向等效记录的不同指针），则算法不保证特定的顺序。 这种关系通常被不同的算法分开。 
 
 比较方法应该满足顺序关系约束 ： 
 
 订单关系应该是： 
 
 
 
 反身：每个项目都应该与自己相同（我猜你最好回0 ） 
 
 
 不对称：如果A小于或等于B且B小于或等于A ，则A和B相等。 
 
 
 传递：如果A小于或等于B且B小于或等于C ，则A小于或等于C. 
 
 
 大多数排序算法隐含地假定了这个约束（他们不检查它们），因此提供了O（n log n）时间复杂度。 如果条件不成立，则根据算法的实施情况，可以得到不同的结果。 
 
 由于并行排序使用MergeSort算法，并且默认排序使用QuickSort算法，因此这两种算法具有不同的行为。 
 
 相关主题：大多数排序算法不稳定。 如果两个项目是“相等的”，那么不保证如果A被放置在原始数组中的A'之前，则A将被放置在结果数组中的A'之前。 

If one runs the program in TryJava8, I get the correctly sorted array. I think you probably printed the input (fruits) instead of the output (arrayFruits). This said, you opened an interesting topic, since in general, you are right a sorting algorithm does not guarantee the full order. In general for large arrays, if two elements are equivalent, but not the same (for instance a different pointer to an equivalent record), the algorithms do not guarantee a specific order. This said ties are in general broken differently by different algorithms.
 
A compare method should satisfy the order relation constraints:
 
An order relation should be:
 
 
 
reflexive: every item should be equal to itself (you better return 0 I guess)
 
 
asymmetrical: if A is less than or equal to B and B is less than or equal to A, A and B are equal.
 
 
transitive: if A is less than or equal to B and B is less than or equal to C, A is less than or equal to C.
 
 
Most of the sorting algorithms assume this constraints implicitly (they don't check them) and thus offer a O(n log n) time complexity. If the condition does not hold, depending on the implementation of the algorithm, one obtains different results.
 
Since a parallel sort uses the MergeSort algorithm, and a default sort uses the QuickSort algorithm, the two algorithms have different behavior.
 
A relevant topic: most sorting algorithms are not stable. Say two items are "equal", then it is not guaranteed that if A was placed before A' in the original array, A will be placed before A' in the resulting array.