#include <bits/stdc++.h>
using namespace std;
int main(){
    int a[15]={0},m=0,n,e=0;
    cin>>n;
    for(m=0;m<n;m++){
    	cin>>a[m];
    }
    for(m=0;m<n;m++){
    	e=e+a[m]*a[m];
    	
}
cout<<e;
}
/**************************************************************
	Problem: 1830
	User: lvrenxiang
	Language: C++
	Result: Accepted
	Time:21 ms
	Memory:2072 kb
****************************************************************/