From 817d04c8d6d91a68b6fe3d1a1df3322468ff8f83 Mon Sep 17 00:00:00 2001
From: Mark Kuang <mark.kuang@careerbuilder.com>
Date: Tue, 16 Oct 2018 21:53:21 +0800
Subject: [PATCH] Solution in Ruby 021

---
 .../021.Merge Two Sorted Lists/Solution.rb    | 39 +++++++++++++++++++
 solution/023.Merge k Sorted Lists/Solution.rb |  0
 2 files changed, 39 insertions(+)
 create mode 100644 solution/021.Merge Two Sorted Lists/Solution.rb
 create mode 100644 solution/023.Merge k Sorted Lists/Solution.rb

diff --git a/solution/021.Merge Two Sorted Lists/Solution.rb b/solution/021.Merge Two Sorted Lists/Solution.rb
new file mode 100644
index 0000000000000..2e01d135e30cb
--- /dev/null
+++ b/solution/021.Merge Two Sorted Lists/Solution.rb	
@@ -0,0 +1,39 @@
+# Definition for singly-linked list.
+# class ListNode
+#     attr_accessor :val, :next
+#     def initialize(val)
+#         @val = val
+#         @next = nil
+#     end
+# end
+
+# @param {ListNode} l1
+# @param {ListNode} l2
+# @return {ListNode}
+def merge_two_lists(l1, l2)
+  return l1 if l2.nil?
+  return l2 if l1.nil?
+
+  head = ListNode.new(0)
+  temp = head
+
+  until l1.nil? && l2.nil?
+    if l1.nil?
+      head.next = l2
+      break
+    elsif l2.nil?
+      head.next = l1
+      break
+    elsif l1.val < l2.val
+      head.next = ListNode.new(l1.val)
+      head = head.next
+      l1 = l1.next
+    else
+      head.next = ListNode.new(l2.val)
+      head = head.next
+      l2 = l2.next
+    end
+  end
+  temp.next
+end
+
diff --git a/solution/023.Merge k Sorted Lists/Solution.rb b/solution/023.Merge k Sorted Lists/Solution.rb
new file mode 100644
index 0000000000000..e69de29bb2d1d