z-sort
题目描述
B. z-sort
time limit per test
1 secondmemory limit per test
256 megabytesinput
standard inputoutput
standard outputA student of z-school found a kind of sorting called z-sort. The array a with n elements are z-sorted if two conditions hold:
- ai≥ai-1 for all even i,
- ai≤ai-1 for all odd i>1.
For example the arrays [1,2,1,2] and [1,1,1,1] are z-sorted while the array [1,2,3,4] isn’t z-sorted.
Can you make the array z-sorted?
Input
The first line contains a single integer n (1≤n≤1000) − the number of elements in the array a.
The second line contains n integers ai (1≤ai≤109) − the elements of the array a.
Output
If it's possible to make the array a z-sorted print n space separated integers ai − the elements after z-sort. Otherwise print the only word "Impossible".
Examples
Input
4
1 2 2 1
Output
1 2 1 2
Input
5
1 3 2 2 5
Output
1 5 2 3 2
题目来源：fps-www.educg.net-codeforce-1-2833.xml.zip；FPS 共享题包，题包内第 787 题。保留原作者与原赛事署名。