CF 286A(Lucky Permutation-数列找规律)

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内容目录
A. Lucky Permutation
time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

A permutation p of size n is the sequence p1, p2, ..., pn,
consisting of n distinct integers, each of them is from 1 to n (1 ≤ pi ≤ n).

A lucky permutation is such permutation p, that any integer i (1 ≤ i ≤ n) meets
this condition ppi = n - i + 1.

You have integer n. Find some lucky permutation p of
size n.

Input

The first line contains integer n (1 ≤ n ≤ 105)
— the required permutation size.

Output

Print "-1" (without the quotes) if the lucky permutation p of size n doesn't
exist.

Otherwise, print n distinct integers p1, p2, ..., pn (1 ≤ pi ≤ n) after
a space — the required permutation.

If there are multiple answers, you can print any of them.

Sample test(s)
input
1
output
1
input
2
output
-1
input
4
output
2 4 1 3
input
5
output
2 5 3 1 4

找规律

如图所示



#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cctype>
#include<iostream>
using namespace std;
int n;
int main()
{
	cin>>n;
	if (n%4>1)
	{
		cout<<"-1n";
		return 0;
	}
	for (int i=1;i<=n/2;i++)
	{
		if (i%2) cout<<i+1<<' ';
		else cout<<(n-i+2)<<' ';
	}
	int m=n/2;
	if (n%4==1)
	{
		cout<<m+1;
		if (m+1<n) cout<<' ';
		m++;
	}
	for (int i=m+1;i<n;i++)
	{
		if ((i-m)%2) cout<<n-i<<' ';
		else cout<<i-1<<' ';
	}
	if (m+1<n) cout<<(n-1);
	cout<<endl;
	return 0;
}