leetcode 2. 两数相加

class Solution(object):
    def addTwoNumbers(self, l1, l2):
        """
        :type l1: ListNode
        :type l2: ListNode
        :rtype: ListNode
        """
        ptr1=l1
        ptr2=l2
        tmp=0
        rtn_node=None
        while ptr1!= None or ptr2!= None:
            tmp_node=ListNode()
            if ptr1==None:
                tmp_node.val=ptr2.val+tmp-(ptr2.val+tmp)/10*10 if ptr2.val+tmp>=10 else ptr2.val+tmp
                tmp=(ptr2.val+tmp)/10
            if ptr2==None:
                tmp_node.val=ptr1.val+tmp-(ptr1.val+tmp)/10*10 if ptr1.val+tmp>=10 else ptr1.val+tmp
                tmp=(ptr1.val+tmp)/10
            if ptr1!=None and ptr2!=None:
                tmp_node.val=ptr1.val+ptr2.val+tmp-(ptr1.val+ptr2.val+tmp)/10*10 if ptr1.val+ptr2.val+tmp>=10 else ptr1.val+ptr2.val+tmp
                tmp=(ptr1.val+ptr2.val+tmp)/10
            if rtn_node==None:
                rtn_node=tmp_node
                ptr3=rtn_node
            else:
                ptr3.next=tmp_node
                ptr3=tmp_node
            try:
                ptr1=ptr1.next
            except:
                pass
            try:
                ptr2=ptr2.next
            except:
                pass 
        if tmp>0:
            tmp_node=ListNode()
            tmp_node.val=tmp
            ptr3.next=tmp_node
            ptr3=tmp_node
        return rtn_node