// 3.11 - exit(param)
begin
var IsPrime: integer → boolean := n → begin
if n < 2 then exit(False);
for var i:=2 to n.Sqrt.Trunc do
if n.Divs(i) then
exit(False);
exit(True);
end;
IsPrime(17).Print;
IsPrime(1).Print;
end.
