Week 08 作业

class Node:  def __init__(self, data):    self.data = data    self.next = None    def is_intersect(l1, l2):  if l1 is None or l2 is None:    return False  p1, p2 = l1, l2  last1, last2 = None, None  while p1.next is not None:    last1 = p1    p1 = p1.next  while p2.next is not None:    last2 = p2    p2 = p2.next  return True if last1 == last2 else False
def find_first_cross_node(l1, l2):  p1, p2 = l1, l2  len1, len2 = 0, 0  while p1.next:    len1 += 1    p1 = p1.next  while p2.next:    len2 += 1    p2 = p2.next   if len1 > len2:    tmp_len = len1 - len2    for _ in range(tmp_len):      l1 = l1.next    for _ in range(len1 - tmp):      if l1 == l2:        return l1      l1 = l1.next      l2 = l2.next    else:      tmp_len = len2 - len1      for _ in range(tmp_len):        l2 = l2.next      for _ in range(len2 - tmp):        if l1 == l2:          return l2        l1 = l1.next        l2 = l2.next