FACTORIAL OF A NUMBER

       IDENTIFICATION DIVISION.
       PROGRAM-ID. FACTORIAL.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       77 N PIC 9(4).
       77 A PIC S9(4) VALUE 0.
       77 F PIC 9(4) VALUE 1.
       PROCEDURE DIVISION.
       PARA.
           DISPLAY "ENTER A NUMBER.".
           ACCEPT N.
           PERFORM PARA1 UNTIL A = N.
           DISPLAY "THE FACTORIAL IS".
           DISPLAY F.
           STOP RUN.
       PARA1.
           ADD 1 TO A.
           COMPUTE F = F * A.