add-two-numbers.rb

Author: Shalaahuddien

2-add-two-numbers/2-add-two-numbers.rb

@@ -0,0 +1,36 @@
+# 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)
+    dummy = ListNode.new(0)
+    current = dummy
+    carry = 0
+    
+    while l1 || l2 || carry != 0
+        sum = carry
+        if l1
+            sum += l1.val
+            l1 = l1.next
+        end
+        if l2
+            sum += l2.val
+            l2 = l2.next
+        end
+        
+        carry = sum / 10
+        sum = sum % 10
+        current.next = ListNode.new(sum)
+        current = current.next
+    end
+    
+    dummy.next
+end