* Tính tổng 

program Tinh_tong;

uses crt;

var i,n: Integer;

     Tong : Longint;

Begin

clrscr;

write('Nhap n :') ; readln(n);

Tong:=0;

for i:=1 to n do Tong :=Tong +i;

writeln ( 'Tong cua cac so tu 1 den n la:',Tong);

readln;

end.

*Tính Tích

program Tinh_tich;

uses crt;

var i,n: Integer;

     Tich : Longint;

Begin

clrscr;

write('Nhap n :') ; readln(n);

Tich:=0;

for i:=1 to n do Tich :=Tich *i;

writeln ( 'Tich cua cac so tu 1 den n la:',Tich);

readln;

end.

$#TrumFlorentino$

uses crt;

var i,n,s,t: integer;

begin

 clrscr;

  write ('nhap vao n: ');  readln (n);

  t:=1;

  for i:=1 to n do

  begin

  t:=t*i;

  s:=s+i;

  end;

  writeln ('tong: ',s);

  writeln ('tich: ',t);

 readln;

end.