RosettaCodeData/Task/Stern-Brocot-sequence/Fortran/stern-brocot-sequence-1.f
2019-09-12 10:33:56 -07:00

31 lines
623 B
Fortran

* STERN-BROCOT SEQUENCE - FORTRAN IV
DIMENSION ISB(2400)
NN=2400
ISB(1)=1
ISB(2)=1
I=1
J=2
K=2
1 IF(K.GE.NN) GOTO 2
K=K+1
ISB(K)=ISB(K-I)+ISB(K-J)
K=K+1
ISB(K)=ISB(K-J)
I=I+1
J=J+1
GOTO 1
2 N=15
WRITE(*,101) N
101 FORMAT(1X,'FIRST',I4)
WRITE(*,102) (ISB(I),I=1,15)
102 FORMAT(15I4)
DO 5 J=1,11
JJ=J
IF(J.EQ.11) JJ=100
DO 3 I=1,K
IF(ISB(I).EQ.JJ) GOTO 4
3 CONTINUE
4 WRITE(*,103) JJ,I
103 FORMAT(1X,'FIRST',I4,' AT ',I4)
5 CONTINUE
END