var a:array[1..10000] of longint;
    n,s,i:longint;
begin
read(n);
for i:=1 to n do
read(a[i]);
for i:=1 to n do
s:=s+a[i]*a[i];
write(s);
end.
/**************************************************************
	Problem: 1830
	User: admin
	Language: Pascal
	Result: Wrong Answer
****************************************************************/