alternative sort of array数组交替排序

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 
 4 const int maxn=10005;
 5 
 6 int main()
 7 {
 8     int t;
 9     cin>>t;
10     while(t--)
11     {
12         int n;
13         int a[maxn];
14         cin>>n;
15         for(int i=0;i<n;i++)
16         {
17             cin>>a[i];
18         }
19         sort(a,a+n);
20         int head=0;
21         int tail=n-1;
22         while(head<tail)//双索引想法
23         {
24             cout<<a[tail--]<<" ";
25             cout<<a[head++]<<" ";
26         }
27         if(n%2!=0)//对性质的讨论，单独处理
28             cout<<a[head]<<endl;
29         else
30             cout<<endl;
31 
32     }
33     return 0;
34 }