[BOJ 6496] Cyclic antimonotonic permutations

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Points: 4
Time limit: 2.0s
Memory limit: 128M

Problem types
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Assembly, Awk, C, C++, Java, Pascal, Perl, Python, Sed, Text

A permutation is a sequence of integers which contains each integer from 1 to n exactly once. In this problem we are looking for permutations with special properties:</p>

  1. Antimonotonic: for each consecutive 3 values pi-1, pi, pi+1 (1 < i < n), pi should either be the smallest or the biggest of the three values.
  2. Cyclic: The permutation should consist of only one cycle, that is, when we use pi as a pointer from i to pi, it should be possible to start at position 1 and follow the pointers and reach all n positions before returning to position 1.
## 입력 형식

The input file contains several test cases. Each test case consists of a line containing an integer n, (3 ≤ n ≤ 106), the number of integers in the permutation. Input is terminated by n=0.

출력 형식

For each test case print a permutation of the integers 1 to n which is both antimonotonic and cyclic. In case there are multiple solutions, you may print any one. Separate all integers by whitespace characters.

예제 입력

3
5
10
0

예제 출력

3 1 2
4 5 2 3 1
6 10 2 9 3 5 4 7 1 8

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