PROGRAM Half_Adder
!-----------------------------------------------------------------------
! Program to calculate the outputs from a logical circuit that
! represents a binary half-adder.  Variables used are:
!    A, B       : the two logical inputs to the circuit
!    Sum, Carry : the two logical outputs
!
! Input:   The two logical inputs A and B
! Output:  The two logical outputs Sum and Carry, which represent the
!          sum and carry that result when the input values are added
!-----------------------------------------------------------------------

  IMPLICIT NONE
  LOGICAL :: A, B, Sum, Carry

  PRINT *, "Enter logical inputs A and B:"
  READ *, A, B
  Sum = (A .OR. B) .AND. .NOT. (A .AND. B)
  Carry = A .AND. B
  PRINT *, "Carry, Sum =", Carry, Sum

END PROGRAM Half_Adder