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1155 Heap Paths (30分)
In computer science, a heap is a specialized tree-based data structure that satisfies the heap property: if P is a parent node of C, then the key (the value) of P is either greater than or equal to (in a max heap) or less than or equal to (in a min heap) the key of C. A common implementation of a heap is the binary heap, in which the tree is a complete binary tree. (Quoted from Wikipedia at https://en.wikipedia.org/wiki/Heap_(data_structure))
One thing for sure is that all the keys along any path from the root to a leaf in a max/min heap must be in non-increasing/non-decreasing order.
Your job is to check every path in a given complete binary tree, in order to tell if it is a heap or not.
Each input file contains one test case. For each case, the first line gives a positive integer N (1
For each given tree, first print all the paths from the root to the leaves. Each path occupies a line, with all the numbers separated by a space, and no extra space at the beginning or the end of the line. The paths must be printed in the following order: for each node in the tree, all the paths in its right subtree must be printed before those in its left subtree.
Finally print in a line Max Heap
if it is a max heap, or Min Heap
for a min heap, or Not Heap
if it is not a heap at all.
8
98 72 86 60 65 12 23 50
98 86 23
98 86 12
98 72 65
98 72 60 50
Max Heap
8
8 38 25 58 52 82 70 60
8 25 70
8 25 82
8 38 52
8 38 58 60
Min Heap
8
10 28 15 12 34 9 8 56
10 15 8
10 15 9
10 28 34
10 28 12 56
Not Heap
思路:一个完整二叉树 是很容易用一个一维数组处理的,pos*2 到左子节点,pos*2+1到右子结点。递归遍历所有结点并把经过节点保存下来。因为路径可能会结点都相等,以至于无法判断最大堆还是最小堆,所以把这些路径保存下来整体判断。
Code:
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