Program mod_modulo 
  IMPLICIT NONE
  INTEGER :: a = -100, p = 7
  DO a = -100, 100, 29
     DO p = -7, 7, 5
        WRITE(*,*) 'Original values of a and p: ', a, p
        WRITE(*,*)
        WRITE(*,*) 'MOD     - Remainder of a modulo p: &
 		   &', MOD(a,p)
        WRITE(*,*) 'MODULO  - a modulo p             : &
 		   &', MODULO(a,p)
        READ(*,*)
    END DO
  END DO
  STOP
END PROGRAM mod_modulo