c:/gdsf/web/fuentes_pascal/factorial.pas

PROGRAM EJER53;
USES CRT;
VAR temp, num, fac : LONGINT;
BEGIN
CLRSCR;
fac := 1;
temp := num;
WRITE ('Introduzca un numero -> ');
READLN (num);
temp := num;
WHILE num >= 1 DO
        BEGIN
        fac := fac * num;
        num := num - 1;
        END;
WRITE ('El factorial de ');
WRITE (temp);
WRITE (' es ');
WRITE (fac);
END.