1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24# Definition for singly-linked list. # class ListNode: # def __init__(self, x): # self.val = x # self.next = None class Solution: def getIntersectionNode(self, headA: ListNode, headB: ListNode) -> ListNode: if headA == None or headB == None: return None a = headA b = headB while a != b: if a == None: a = headB else: a = a.next if b == None: b = headA else: b = b.next return a