tpw (n!=1+2+3+.......+n的code)

N factorial is defined as :
N! = 1 X 2 X 3 X . . . X N


The following is a simple program written in tpw using "repeat . . . until" for your reference :

uses wincrt;

var
　n, i, fact : real;

begin
　write('Input a positive integer: ');
　readln(n);
　i:=0;
　fact:=1;
　repeat
　　i:=i+1;
　　fact:=fact*i;
　until i=n;
　writeln(n:1:0, '! = ', fact:1:0);
end.


If you really want to find the value of 1 + 2 + 3 + . . . + N,
then change fact:=1; to fact:=0;
and change fact:=fact*i; to fact:=fact+i;