'**********************************************
'* Geatest common divisor and Smallest common *
'*     multiple of several integer numbers    *
'* ------------------------------------------ *
'* Ref.: "Mathematiques en Turbo-Pascal By    *
'*        M. Ducamp and A. Reverchon (2),     *
'*        Eyrolles, Paris, 1988" [BIBLI 05].  *
'* ------------------------------------------ *
'* Sample run:                                *
'*                                            *
'* GCD and SCM of integer numbers:            *
'*                                            *
'* First number: 9936                         *
'* Next number : 414                          *
'* Next number : 3174                         *
'* Next number : 0                            *
'*                                            *
'* GCD =  138                                 *
'* SCM =  228528                              *
'*                                            *
'*               BASIC Version By J-P Moreau  *
'*                    (www.jpmoreau.fr)       *
'**********************************************
  cls
  print
  print " GCD and SCM of integer numbers:"
  print
  input " First number: ", pg : pp=pg
10 input " Next number : ", x
  if x>0 then
    a=pg:b=x:gosub 1000: pg=xx   'pg=GCD(pg,x)
    a=pp:b=x:gosub 1000
    pp=pp*x/xx                   'xx=GCD(pp,x)
  end if
  if x<>0 then goto 10
  print
  print " GCD = "; pg
  print " SCM = "; pp
  print
end

'xx=GCD(a,b)
1000 a = int(abs(a))
  b = int(abs(b))
  if a>1e10 or b>1e10 then xx=1 : return
  if a=0 or b=0 then xx=1 : return
  if a<b then
    temp=a : a=b : b=temp
  end if

1010 r=a-b*int(a/b)
    a=b : b=r
  if abs(r)>1e-10 then goto 1010
  xx = a
return

' end of file gcd.bas