program tinh_tong;
uses crt;
var n:integer;
{---Chuong-trinh-con---}
function tong(m:integer):real;
var i:integer;
begin
tong:=0;
for i:=1 to m do
tong:=tong+1/i;
end;
{---Chuong-trinh-chinh---}
BEGIN
clrscr;
write('Nhap n: '); readln(n);
write('S= ',tong(n):0:3);
readln;
end.