// Rosetta Code problem: https://rosettacode.org/wiki/Farey_sequence
// by Jjuanhdez, 06/2022

for i = 1 to 11
    print "F", i, " = ";
    farey(i, FALSE)
next i
print
for i = 100 to 1000 step 100
    print "F", i;
    if i <> 1000 then print " "; else print ""; : fi
    print " = ";
    farey(i, FALSE)
next i
end

sub 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 = cont + 1
    if n < 12 then print a, "/", b, " "; : fi

    while ((c <= n) and not descending) or ((a > 0) and descending)
        aa = a : bb = b : cc = c : dd = d
        k = int((n + b) / d)
        a = cc : b = dd : c = k * cc - aa : d = k * dd - bb
        cont = cont + 1
        if n < 12 then print a, "/", b, " "; : fi
    end while

    if n < 12 then print else print cont using("######") : fi
end sub