PROGRAM factorial ! ! Author: Br. David Carlson ! ! Date: February 8, 2000 ! ! This program prompts the user to enter integers, with a negative used to ! signal the end of data. For every nonnegative number entered, the program ! prints its factorial. IMPLICIT NONE INTEGER::num, fact, k WRITE (*, *) 'Enter a nonnegative integer (or a negative one to quit)' READ (*, *) num DO WHILE (num >= 0) fact = 1 DO k = 2, num fact = fact * k END DO WRITE (*, *) 'This number has factorial: ', fact WRITE (*, *) 'Enter a nonnegative integer (or a negative one to quit)' READ (*, *) num END DO END PROGRAM