uses crt;
var n : integer;
function gt( K : integer) : real;
var i,j,s : integer;
m : real;
begin clrscr;
for i:=1 to n do begin s:=1;
for j:=1 to i do s:=s*j;
m:=m+1/s end;
gt:=m;
end;
begin clrscr;
write('Nhap n:'); readln(n);
write('Tong do la :', gt(n):2:3);
readln
end.