In PHP, arrays are so powerful that they include all of these data structures, so you don't need to pay much attention to them. Over time, the concept of data structures has faded, not that THERE are no data structures in PHP.

There are two kinds of priority queues: the maximum priority queue, the current largest element priority queue; Minimum priority queue, the current smallest element is queued first. PriorityQueue is implemented by using a small top heap represented by an array. The specific structure is as follows: First, any node is smaller than its left and right children. In addition, for any node, suppose its subscript is n: left child: 2 * n + 1 right child: 2 * n + 2 parent: (n + 1) / 21 is constructed as...