PAT (Advanced Level) Practise 1099 Build A Binary Search Tree (30)
2017-07-03 14:52
531 查看
1099. Build A Binary Search Tree (30)
时间限制100 ms
内存限制
65536 kB
代码长度限制
16000 B
判题程序
Standard
作者
CHEN, Yue
A Binary Search Tree (BST) is recursively defined as a binary tree which has the following properties:
The left subtree of a node contains only nodes with keys less than the node's key.
The right subtree of a node contains only nodes with keys greater than or equal to the node's key.
Both the left and right subtrees must also be binary search trees.
Given the structure of a binary tree and a sequence of distinct integer keys, there is only one way to fill these keys into the tree so that the resulting tree satisfies the definition of a BST. You are supposed to output the level order traversal sequence
of that tree. The sample is illustrated by Figure 1 and 2.
Input Specification:
Each input file contains one test case. For each case, the first line gives a positive integer N (<=100) which is the total number of nodes in the tree. The next N lines each contains the left and the right children of a node in the format "left_index right_index",
provided that the nodes are numbered from 0 to N-1, and 0 is always the root. If one child is missing, then -1 will represent the NULL child pointer. Finally N distinct integer keys are given in the last line.
Output Specification:
For each test case, print in one line the level order traversal sequence of that tree. All the numbers must be separated by a space, with no extra space at the end of the line.
Sample Input:
9 1 6 2 3 -1 -1 -1 4 5 -1 -1 -1 7 -1 -1 8 -1 -1 73 45 11 58 82 25 67 38 42
Sample Output:
58 25 82 11 38 67 45 73 42
题意:给你一个固定好了的有n个节点的树,给你n个值,将它们插入树中,使得树是一棵二叉搜索树解题思路:按照中序遍历将数字从小到大插入即可
#include <iostream> #include <cstdio> #include <cstring> #include <string> #include <algorithm> #include <vector> #include <queue> #include <stack> #include <map> #include <set> #include <cmath> using namespace std; #define LL long long const int INF = 0x3f3f3f3f; int n,now[105][5],cnt,a[105],ans[105]; void dfs(int k) { if(now[k][0]!=-1) dfs(now[k][0]); ans[k]=a[cnt++]; if(now[k][1]!=-1) dfs(now[k][1]); } int main() { while(~scanf("%d",&n)) { for(int i=0;i<n;i++) scanf("%d%d",&now[i][0],&now[i][1]); for(int i=0;i<n;i++) scanf("%d",&a[i]); sort(a,a+n); cnt=0; dfs(0); queue<int>q; q.push(0); while(!q.empty()) { int pre=q.front(); q.pop(); printf("%s%d",pre?" ":"",ans[pre]); if(now[pre][0]!=-1) q.push(now[pre][0]); if(now[pre][1]!=-1) q.push(now[pre][1]); } printf("\n"); } return 0; }
相关文章推荐
- PAT (Advanced Level) Practise 1099 Build A Binary Search Tree (30)
- 1064. Complete Binary Search Tree (30)【二叉树】——PAT (Advanced Level) Practise
- PAT (Advanced Level) Practise 1064 Complete Binary Search Tree (30)
- Pat(Advanced Level)Practice--1099(Build A Binary Search Tree )
- PAT (Advanced Level) Practise 1064 Complete Binary Search Tree (30)
- 1064. Complete Binary Search Tree (30)【二叉树】——PAT (Advanced Level) Practise
- PAT (Advanced Level) 1064. Complete Binary Search Tree (30)
- 1043. Is It a Binary Search Tree (25)【二叉树】——PAT (Advanced Level) Practise
- PAT (Advanced Level) Practise 1043 Is It a Binary Search Tree (25)
- 浙大PAT (Advanced Level) Practise 1043 Is It a Binary Search Tree (25)
- 【PAT】【Advanced Level】1064. Complete Binary Search Tree (30)
- PAT 1099-Build A Binary Search Tree (30)
- PAT (Advanced Level) 1064. Complete Binary Search Tree (30) 递归建立CBST
- PAT (Advanced Level) Practise 1043 Is It a Binary Search Tree (25)
- PAT (Advanced Level) Practise 1123 Is It a Complete AVL Tree (30)
- 1099. Build A Binary Search Tree (30)
- PAT 1099 Build A Binary Search Tree
- PAT (Advanced Level) Practise 1110 Complete Binary Tree (25)
- pat 1099 Build A Binary Search Tree
- PAT (Advanced Level) Practise 1102 Invert a Binary Tree (25)