Farey sequence: Difference between revisions

=={{header|BASIC256}}==

<lang BASIC256>for i = 1 to 11

print "F"; i; " = ";

call farey(i, FALSE)

next i

print

for i = 100 to 1000 step 100

print "F"; i;

if i <> 1000 then print " "; else print "";

print " = ";

call farey(i, FALSE)

next i

end

subroutine farey(n, descending)

a = 0 : b = 1 : c = 1 : d = n : k = 0

cont = 0

if descending = TRUE then

a = 1 : c = n -1

end if

cont += 1

if n < 12 then print a; "/"; b; " ";

while ((c <= n) and not descending) or ((a > 0) and descending)

aa = a : bb = b : cc = c : dd = d

k = (n + b) \ d

a = cc : b = dd : c = k * cc - aa : d = k * dd - bb

cont += 1

if n < 12 then print a; "/"; b; " ";

end while

if n < 12 then print else print rjust(cont,7)

end subroutine</lang>

{{out}}

<pre>Same as FreeBASIC entry.</pre>