def find_cross(h_lines, v_lines):
h_queue, v_queue = build_queue(h_lines, v_lines)
# print "h_queue", h_queue.get_keys()
# print "v_queue", v_queue.get_keys()
tree = BinarySearchTree()
points = []
while True:
v_item = v_queue.pop()
if v_item != None:
print "scan", v_item.key
delete_items = []
h_item = h_queue.max()
while h_item != None and h_item.key >= v_item.key:
h_item = h_queue.pop()
if type(h_item.value) != type(0): # start node
if not tree.contains(h_item.value[0]):
print "insert", h_item.value[0], h_item.value[1]
tree.put(h_item.value[0], h_item.value[1])
else: # overlapping start node
end = tree.search(h_item.value[0])
print "overlapping start", h_item.value[0]
if end > h_item.value[1]:
print "update", h_item.value[0], h_item.value[1]
tree.put(h_item.value[0], h_item.value[1]) # update the larger end
else:
print "drop inner section ", h_item.value[1], " within ", end
else: # end node
end = tree.search(h_item.value)
assert end <= h_item.key
if end == h_item.key: # if it's the larger end, remove the y
print "catch the end", end
if h_item.key > v_item.key:
tree.hibbard_deletion(h_item.value)
print "remove", h_item.value, "scan", h_item.key
else:
delete_items.append(h_item.value)
h_item = h_queue.max()
assert v_item.value[1] >= v_item.value[0]
nodes = tree.range_node(v_item.value[0], v_item.value[1])
print "find node in range (", v_item.value[0], v_item.value[1], "):", nodes
for node in nodes:
points.append((v_item.key, node[0]))
print "points", points
print "tree", tree.level_order_traversal()
print "remove", delete_items
v_item_next = h_queue.max()
if v_item_next != None and v_item_next.key < v_item.key: # remove the y when v goes smaller
for node in delete_items:
tree.hibbard_deletion(node)
else:
return points
