P.s it's easy! input n output all prime numbers from 1 to n

//PascalABC.NET
//Версия 3.3, сборка 1611
function isprost(x: integer): boolean;
begin
if x<2 then isprost:=false else
begin
isprost:=true;
for var i:= 2 to round(sqrt(x)) do if x mod i = 0 then isprost:=false;
end;
end;
begin
range(1,ReadInteger()).Where(x->isprost(x)).Println();
end.