c This is a comment PROGRAM QUAD E = 1E-9 READ *, A,B,C IF (A.GE. -E .AND. A.LE.E) THEN PRINT *, 'FIRST COEFFICIENT MUST BE NON-ZERO.' ELSE S = B**2 - 4*A*C IF (S.GT.E) THEN D = S**0.5 X1 = (-B+D)/(2*A) X2 = (-B-D)/(2*A) PRINT *, 'TWO DISTINCT ROOTS:' X1 'AND' X2 ELSE IF (S.GT. -E) THEN X = -B/(2*A) PRINT *, 'TWO COINCIDENT ROOTS',X ELSE PRINT *, 'NO REAL ROOTS.' END IF END IF END SUBROUTINE TEST INTEGER I, NN 123 DO 234 I=1,NNc do something 234 CONTINUE go to 123 GOTO(123, 234, 123, 234, 123), NN ENDC AREA OF A TRIANGLE - HERON'S FORMULAC INPUT - CARD READER UNIT 5, INTEGER INPUTC OUTPUT - LINE PRINTER UNIT 6, REAL OUTPUTC INPUT ERROR DISPAY ERROR OUTPUT CODE 1 IN JOB CONTROL LISTING SUBROUTINE AREA INTEGER A,B,C READ(5,501) A,B,C 501 FORMAT(3I5) IF(A.EQ.0 .OR. B.EQ.0 .OR. C.EQ.0) STOP 1 S = (A + B + C) / 2.0 AREA = SQRT( S * (S - A) * (S - B) * (S - C) ) WRITE(6,601) A,B,C,AREA 601 FORMAT(4H A= ,I5,5H B= ,I5,5H C= ,I5,8H AREA= ,F10.2,12HSQUARE UNITS) STOP END* euclid.f (FORTRAN 77)* Find greatest common divisor using the Euclidean algorithm SUBROUTINE EUCLID PRINT *, 'A?' READ *, NA IF (NA.LE.0) THEN PRINT *, 'A must be a positive integer.' STOP END IF PRINT *, 'B?' READ *, NB IF (NB.LE.0) THEN PRINT *, 'B must be a positive integer.' STOP END IF PRINT *, 'The GCD of', NA, ' and', NB, ' is', NGCD(NA, NB), '.' STOP END FUNCTION NGCD(NA, NB) IA = NA IB = NB 1 IF (IB.NE.0) THEN ITEMP = IA IA = IB IB = MOD(ITEMP, IB) GOTO 1 END IF NGCD = IA RETURN END