Intersection of Two Linked Lists

# 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
        """
        list_dict={}
        while headA:
            list_dict[headA] = 1
            headA = headA.next
        while headB:
            if headB in list_dict:
                return headB
            else:
                headB= headB.next