10分只对了一个点样例全过

#include<bits/stdc++.h>
using namespace std;
const int N=1e6+5;
long long a[N];
int main(){
	long long  n;
	cin>>n;
	for(int i=1;i<=n;++i){
		cin>>a[i];
	}
	sort(a+1,a+n+1);
	long long ans=a[n]*a[n];
	for(int i=1;i<=n/2;++i){
		ans+=(a[i]-a[n-i+1])*(a[i]-a[n-i+1]);
	} 
	if(n%2){
		ans+=(a[n/2]-a[n/2+1])*(a[n/2]-a[n/2+1]);
	}
	cout<<ans<<endl; 
}