def intersect:
.[0] as $A | .[1] as $B
| ($A|length) as $al
| ($B|length) as $bl
| if $al == 0 or $bl == 0 then false
else
($B | bsearch($A[0])) as $b
| if $b >= 0 then true
else [$A[1:], $B[- (1 + $b) :]] | intersect
end
end;