Leetcode 2: Add two numbers linkedlist

leetcode_2_add_2_numbers_linkedlist.rb

Leetcode 2: Add two numbers linkedlist

# Definition for singly-linked list.
# class ListNode
#     attr_accessor :val, :next
#     def initialize(val = 0, _next = nil)
#         @val = val
#         @next = _next
#     end
# end
# @param {ListNode} l1
# @param {ListNode} l2
# @return {ListNode}
def add_two_numbers(l1, l2)
    carry = 0
    curr_list = ListNode.new
    return_list = curr_list
    while (l1!=nil && l2!=nil) do
        t_sum = l1.val + l2.val + carry
        if t_sum > 9
            curr_list.val = t_sum%10
            carry = 1
        else
            curr_list.val = t_sum
            carry = 0
        end
        l1=l1.next
        l2=l2.next
        if l1 || l2
            curr_list.next = ListNode.new 
            curr_list = curr_list.next
        end
    end
    while (l1!=nil) do
        t_sum = l1.val + carry
        if t_sum > 9
            curr_list.val = t_sum%10
            carry = 1
        else
            curr_list.val = t_sum
            carry = 0
        end
        if l1=l1.next
            curr_list.next = ListNode.new 
            curr_list = curr_list.next
        end
    end
    while (l2!=nil) do
        t_sum = l2.val + carry
        if t_sum > 9
            curr_list.val = t_sum%10
            carry = 1
        else
            curr_list.val = t_sum
            carry = 0
        end
        if l2=l2.next
            curr_list.next = ListNode.new 
            curr_list = curr_list.next
        end
    end

    if carry == 1
        curr_list.next = ListNode.new 
        curr_list = curr_list.next
        curr_list.val = 1
    end

    return return_list

    # (0..[l1.count, l2.count].max).each do |i|
    #     if l1[i] && l2[i]
    #         t_sum = l1[i] + l2[i] + carry
    #         if t_sum > 9
    #             out_arr << t_sum%10
    #             carry = 1
    #         else
    #             out_arr << t_sum
    #             carry = 0
    #         end
    #     elsif l1[i]
    #     t_sum = l1[i] + carry
    #         if t_sum > 9
    #             out_arr << t_sum%10
    #             carry = 1
    #         else
    #             out_arr << t_sum
    #             carry = 0
    #         end
    #     elsif l2[i]
    #     t_sum = l2[i] + carry
    #         if t_sum > 9
    #             out_arr << t_sum%10
    #             carry = 1
    #         else
    #             out_arr << t_sum
    #             carry = 0
    #         end
    #     end
    # end
    #carry == 1 ? (out_arr << carry) : out_arr
end