A13374. Constructing the Array
编程题
普及/提高-
知识点
题目描述
You are given an array $a$ of length $n$ consisting of zeros. You perform $n$ actions with this array: during the $i$ -th action, the following sequence of operations appears:
1. Choose the maximum by length subarray (continuous subsegment) consisting only of zeros, among all such segments choose the leftmost one;
2. Let this segment be $[l; r]$ . If $r-l+1$ is odd (not divisible by $2$ ) then assign (set) $a[\frac{l+r}{2}] := i$ (where $i$ is the number of the current action), otherwise (if $r-l+1$ is even) assign (set) $a[\frac{l+r-1}{2}] := i$ .
Consider the array $a$ of length $5$ (initially $a=[0, 0, 0, 0, 0]$ ). Then it changes as follows:
1. Firstly, we choose the segment $[1; 5]$ and assign $a[3] := 1$ , so $a$ becomes $[0, 0, 1, 0, 0]$ ;
2. then we choose the segment $[1; 2]$ and assign $a[1] := 2$ , so $a$ becomes $[2, 0, 1, 0, 0]$ ;
3. then we choose the segment $[4; 5]$ and assign $a[4] := 3$ , so $a$ becomes $[2, 0, 1, 3, 0]$ ;
4. then we choose the segment $[2; 2]$ and assign $a[2] := 4$ , so $a$ becomes $[2, 4, 1, 3, 0]$ ;
5. and at last we choose the segment $[5; 5]$ and assign $a[5] := 5$ , so $a$ becomes $[2, 4, 1, 3, 5]$ .
Your task is to find the array $a$ of length $n$ after performing all $n$ actions. Note that the answer exists and unique.
You have to answer $t$ independent test cases.
1. Choose the maximum by length subarray (continuous subsegment) consisting only of zeros, among all such segments choose the leftmost one;
2. Let this segment be $[l; r]$ . If $r-l+1$ is odd (not divisible by $2$ ) then assign (set) $a[\frac{l+r}{2}] := i$ (where $i$ is the number of the current action), otherwise (if $r-l+1$ is even) assign (set) $a[\frac{l+r-1}{2}] := i$ .
Consider the array $a$ of length $5$ (initially $a=[0, 0, 0, 0, 0]$ ). Then it changes as follows:
1. Firstly, we choose the segment $[1; 5]$ and assign $a[3] := 1$ , so $a$ becomes $[0, 0, 1, 0, 0]$ ;
2. then we choose the segment $[1; 2]$ and assign $a[1] := 2$ , so $a$ becomes $[2, 0, 1, 0, 0]$ ;
3. then we choose the segment $[4; 5]$ and assign $a[4] := 3$ , so $a$ becomes $[2, 0, 1, 3, 0]$ ;
4. then we choose the segment $[2; 2]$ and assign $a[2] := 4$ , so $a$ becomes $[2, 4, 1, 3, 0]$ ;
5. and at last we choose the segment $[5; 5]$ and assign $a[5] := 5$ , so $a$ becomes $[2, 4, 1, 3, 5]$ .
Your task is to find the array $a$ of length $n$ after performing all $n$ actions. Note that the answer exists and unique.
You have to answer $t$ independent test cases.
输入格式
The first line of the input contains one integer $t$ ( $1 \le t \le 10^4$ ) — the number of test cases. Then $t$ test cases follow.
The only line of the test case contains one integer $n$ ( $1 \le n \le 2 \cdot 10^5$ ) — the length of $a$ .
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$ ( $\sum n \le 2 \cdot 10^5$ ).
The only line of the test case contains one integer $n$ ( $1 \le n \le 2 \cdot 10^5$ ) — the length of $a$ .
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$ ( $\sum n \le 2 \cdot 10^5$ ).
输出格式
For each test case, print the answer — the array $a$ of length $n$ after performing $n$ actions described in the problem statement. Note that the answer exists and unique.
输入输出样例
输入 #1
6 1 2 3 4 5 6
输出 #1
1 1 2 2 1 3 3 1 2 4 2 4 1 3 5 3 4 1 5 2 6