题目链接:
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
题意:把数列变成要求的那样,太简单就不好说了;
AC代码:
/*2014300227 652B - 6 GNU C++11 Accepted 15 ms 2168 KB*/ #include <bits/stdc++.h> using namespace std; int a[2000]; int main() { int n; scanf("%d",&n); for(int i=1;i<=n;i++) { scanf("%d",&a[i]); } sort(a+1,a+n+1); if(n%2==0) { for(int i=1;i<=n/2;i++) { printf("%d ",a[i]); printf("%d ",a[n-i+1]); } } else { for(int i=1;i<=n/2;i++) { printf("%d ",a[i]); printf("%d ",a[n-i+1]); } printf("%d",a[n/2+1]); } return 0; }