#include <bits/stdc++.h>
using namespace std;
int n,a[1000],s;
int main(){
	cin>>n;
	for (int i=0;i<n;i++){
		cin>>a[i];
		s=s+a[i]*a[i];
	}
	cout<<s;
	return 0;
}

/**************************************************************
	Problem: 1830
	User: admin
	Language: C++
	Result: Accepted
	Time:25 ms
	Memory:2076 kb
****************************************************************/