1147 Heaps(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)
Your job is to tell if a given complete binary tree is a heap.
Input Specification:
Each input file contains one test case. For each case, the first line gives two positive integers: M (≤ 100), the number of trees to be tested; and N (1 < N ≤ 1,000), the number of keys in each tree, respectively. Then M lines follow, each contains N distinct integer keys (all in the range of int), which gives the level order traversal sequence of a complete binary tree.
Output Specification:
For each given tree, 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. Then in the next line print the tree's postorder traversal sequence. All the numbers are separated by a space, and there must no extra space at the beginning or the end of the line.
Sample Input:
3 8
98 72 86 60 65 12 23 50
8 38 25 58 52 82 70 60
10 28 15 12 34 9 8 56
Sample Output:
Max Heap
50 60 65 72 12 23 86 98
Min Heap
60 58 52 38 82 70 25 8
Not Heap
56 12 34 28 9 8 15 10
题意:
给定层序遍历的树,判断是否为大小堆。
思路:
先将输出转化为一棵树,这样就好做了,就是比较暴力
看看 柳婼 の blog 是怎么做的
题解:
#include<cstdlib> #include<cstdio> #include<vector> using namespace std; struct node { int value; int left; int right; }; bool isMaxHeap(vector<node> nodes, int now) { bool isMax = true; < nodes.size()) { ].value) { isMax = false; } else { )) { isMax = false; } } } + < nodes.size()) { + ].value) { isMax = false; } else { + )) { isMax = false; } } } return isMax; } bool isMinHeap(vector<node> nodes, int now) { bool isMin = true; < nodes.size()) { ].value) { isMin = false; } else { )) { isMin = false; } } } + < nodes.size()) { + ].value) { isMin = false; } else { + )) { isMin = false; } } } return isMin; } void PostOrder(vector<node> nodes, int now) { < nodes.size()) { PostOrder(nodes, now * ); } + < nodes.size()) { PostOrder(nodes, now * + ); } //nodes[nodes.size() - 1]这个结点不一定是先输出的。 printf( ? "\n" : " "); } int main() { int n, m; scanf("%d %d", &n, &m); ; i < n; i++) { vector<node> nodes(m+); ; j <= m; j++) { scanf("%d", &nodes[j].value); nodes[j].left = j * ; nodes[j].right = j * + ; } )) { printf("Max Heap\n"); } )) { printf("Min Heap\n"); } else { printf("Not Heap\n"); } PostOrder(nodes, ); } ; }