1064. Complete Binary Search Tree (30)

Complete 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.

A Complete Binary Tree (CBT) is a tree that is completely filled, with the possible exception of the bottom level, which is filled from left to right.

Now given a sequence of distinct non-negative integer keys, a unique BST can be constructed if it is required that the tree must also be a CBT. You are supposed to output the level order traversal sequence of this BST.

Input Specification:

Each input file contains one test case. For each case, the first line contains a positive integer N (<=1000). Then N distinct non-negative integer keys are given in the next line. All the numbers in a line are separated by a space and are no greater than 2000.

Output Specification:

For each test case, print in one line the level order traversal sequence of the corresponding complete binary search tree. All the numbers in a line must be separated by a space, and there must be no extra space at the end of the line.

Sample Input:

10

1 2 3 4 5 6 7 8 9 0

Sample Output:

6 3 8 1 5 7 9 0 2 4

#include<iostream>
#include<algorithm>
using namespace std;
int num[1005];
int temp[1005],index1=1;
int ans[1005];
int n;
void zhongxu(int now)
{
if (now>n)
return  ;
zhongxu(now*2);
temp[index1++]=now;
zhongxu(now*2+1);
}
int main()
{
cin>>n;
for (int i=1;i<=n;i++)
cin>>num[i];
sort(num+1,num+n+1);
zhongxu(1);
for (int i=1;i<index1;i++)
ans[temp[i]]=num[i];
for (int i=1;i<index1-1;i++)
cout<<ans[i]<<" ";
cout<<ans[index1-1];
return 0;
}