*> Open COBOL -- https://open-cobol.sourceforge.io/
*> This program computes the factorial of n
*> Run it in the terminal with these two commands:
*> 1. $ cobc -x factorial.cob
*> 2. $ ./factorial
IDENTIFICATION DIVISION.
PROGRAM-ID. Factorial.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 n BINARY-LONG.
01 i BINARY-LONG.
01 prod BINARY-LONG VALUE 1.
PROCEDURE DIVISION.
DISPLAY "Enter a positive integer (e.g. 10)"
ACCEPT n
PERFORM VARYING i FROM 1 BY 1 UNTIL i > n
MULTIPLY prod BY i GIVING prod
END-PERFORM
DISPLAY "The factorial of " n " is " prod ".".