LeetCode/2_AddTwoNumbers_LeetCodeDriver.py at master · Shinnnyshinshin/LeetCode · GitHub

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#-------------------------------------------------------------------------------
#
#-------------------------------------------------------------------------------
# By Will Shin
#
#-------------------------------------------------------------------------------
#    LeetCode prompt
#-------------------------------------------------------------------------------

"""
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.

Example:

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
Explanation: 342 + 465 = 807
"""
# #
#-------------------------------------------------------------------------------
#    Approach
#-------------------------------------------------------------------------------

"""

"""

#-------------------------------------------------------------------------------
#    Solution
#-------------------------------------------------------------------------------

from mymodules import LinkedLists as myll

def my_two_sum_helper(node1, node2, carryover):
    mysum = None
    if not node1 and not node2 and carryover == 0:
        return(mysum)
    else:
        mysum = 0
        if carryover >= 0:
            mysum += carryover
        if node1:
            mysum += node1.val
        if node2:
            mysum += node2.val
    return(mysum)


def my_twosum(list1_current, list2_current):
    carryover = 0
    head_node = None
    current_node = None
    # keep doing while the nodes are all valid
    returned = my_two_sum_helper(list1_current, list2_current, carryover)
    while returned is not None:
        to_add = returned % 10
        carryover = returned // 10
        if head_node is None:
            head_node = myll.ListNode(to_add)
            current_node = head_node
        else:
            current_node.next = myll.ListNode(to_add)
            current_node = current_node.next
        if list1_current is not None:
            list1_current = list1_current.next
        if list2_current is not None:
            list2_current = list2_current.next
        returned = my_two_sum_helper(list1_current, list2_current, carryover)
    return(head_node)

def print_nodes(headnode):
    to_return = []
    current_node = headnode
    while current_node is not None:
        to_return.append(current_node.val)
        current_node = current_node.next
    return(to_return)
#-------------------------------------------------------------------------------
#    Main Leetcode Input Driver
#-------------------------------------------------------------------------------

class Solution(object):
    def addTwoNumbers(self, l1, l2):
        return my_twosum(l1, l2)

#-------------------------------------------------------------------------------
#    Unit Test
#-------------------------------------------------------------------------------

import unittest

class TestSolution(unittest.TestCase):

    def test_Example(self):
        list1 = myll.LinkedList()
        list1.addList([2, 4, 3])
        list2 = myll.LinkedList()
        list2.addList([5, 6, 4])
        headnode = Solution().addTwoNumbers(list1.head, list2.head)
        to_compare = print_nodes(headnode)
        self.assertEqual(to_compare, [7, 0, 8])

    def test_Zeros(self):
        list1 = myll.LinkedList()
        list1.addList([0])
        list2 = myll.LinkedList()
        list2.addList([0])
        headnode = Solution().addTwoNumbers(list1.head, list2.head)
        to_compare = print_nodes(headnode)
        self.assertEqual(to_compare, [0])

unittest.main()