C++ :

#include<bits/stdc++.h>
using namespace std;

int main(){
	int n,a[61],i,j,k,t;
	cin>>n;
	for(i = 0;i < n;i++){
		cin>>a[i];
	}
	
	//排序
	for(i = 1;i < n;i++) {
		for(j = 0;j < n - i;j++){
			if(a[j] > a[j + 1]){
				t = a[j];
				a[j] = a[j + 1];
				a[j + 1] = t;
			}
		}
	}
	//152 154 157 159 160 162 163 
	//152 157 160 163 162 159 154
	for(i = 0;i < n;i = i + 2){
		cout<<a[i]<<" ";
	}
	
	for(i = n - 2;i >= 0;i = i - 2){
		cout<<a[i]<<" ";
	}
}

Python :

n=int(input())
a=input().split()
a=list(map(int,a))
a=sorted(a)
a.reverse()
b=[0]*n
m=n//2
b[m]=a[0]
for i in range(1,n,2):
    b[m+(i//2)+1]=a[i]
    b[m-(i//2+1)]=a[i+1]
for i in b:
    print(i,end=" ")