[160. Intersection of Two Linked Lists] #leetcode

160_1023.py

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
    def getIntersectionNode(self, headA, headB):
        """
        :type head1, head1: ListNode
        :rtype: ListNode
        """
        # corner case if any list is empty
        if headA is None or headB is None:
            return None
        
        # initialize end nodes and head nodes
        pA = headA
        pB = headB
        
        while pA is not pB:
            pA = headB if pA is None else pA.next
            pB = headA if pB is None else pB.next
            
        return pA