uses crt;
var i,n:integer;
p:real;
begin
clrscr;
write('nhap n='); readln(n);
p:=1;
for i:=1 to n do
p:=p*(1/i);
writeln('tich la: ',p:4:2);
readln;
end.
program tinhtich;
uses crt;
var s:real;
n:integer;
begin
clrscr;
write('nhap n:');readln(n);
s:=1;
for i:=1 to n do
s:=s*(1/i);
writeln('tong s la:',s:4:2);
readln
end.