diff --git a/README.md b/README.md
index 8beabb94..4f624e44 100644
--- a/README.md
+++ b/README.md
@@ -744,6 +744,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 2161. Partition Array According to Given Pivot                                      | [Link](https://leetcode.com/problems/partition-array-according-to-given-pivot/)                                      | [Link](./lib/medium/2161_partition_array_according_to_given_pivot.rb)                                      | [Link](./test/medium/test_2161_partition_array_according_to_given_pivot.rb)                                      |
 | 2165. Smallest Value of the Rearranged Number                                       | [Link](https://leetcode.com/problems/smallest-value-of-the-rearranged-number/)                                       | [Link](./lib/medium/2165_smallest_value_of_the_rearranged_number.rb)                                       | [Link](./test/medium/test_2165_smallest_value_of_the_rearranged_number.rb)                                       |
 | 2177. Find Three Consecutive Integers That Sum to a Given Number                    | [Link](https://leetcode.com/problems/find-three-consecutive-integers-that-sum-to-a-given-number/)                    | [Link](./lib/medium/2177_find_three_consecutive_integers_that_sum_to_a_given_number.rb)                    | [Link](./test/medium/test_2177_find_three_consecutive_integers_that_sum_to_a_given_number.rb)                    |
+| 2181. Merge Nodes in Between Zeros                                                  | [Link](https://leetcode.com/problems/merge-nodes-in-between-zeros/)                                                  | [Link](./lib/medium/2181_merge_nodes_in_between_zeros.rb)                                                  | [Link](./test/medium/test_2181_merge_nodes_in_between_zeros.rb)                                                  |
 | 2425. Bitwise XOR of All Pairings                                                   | [Link](https://leetcode.com/problems/bitwise-xor-of-all-pairings/)                                                   | [Link](./lib/medium/2425_bitwise_xor_of_all_pairings.rb)                                                   | [Link](./test/medium/test_2425_bitwise_xor_of_all_pairings.rb)                                                   |
 | 2429. Minimize XOR                                                                  | [Link](https://leetcode.com/problems/minimize-xor/)                                                                  | [Link](./lib/medium/2429_minimize_xor.rb)                                                                  | [Link](./test/medium/test_2429_minimize_xor.rb)                                                                  |
 | 2657. Find the Prefix Common Array of Two Arrays                                    | [Link](https://leetcode.com/problems/find-the-prefix-common-array-of-two-arrays/)                                    | [Link](./lib/medium/2657_find_the_prefix_common_array_of_two_arrays.rb)                                    | [Link](./test/medium/test_2657_find_the_prefix_common_array_of_two_arrays.rb)                                    |
diff --git a/leetcode-ruby.gemspec b/leetcode-ruby.gemspec
index 0b1bef24..db4674c3 100644
--- a/leetcode-ruby.gemspec
+++ b/leetcode-ruby.gemspec
@@ -5,7 +5,7 @@ require 'English'
 ::Gem::Specification.new do |s|
   s.required_ruby_version = '>= 3.0'
   s.name = 'leetcode-ruby'
-  s.version = '9.0.9'
+  s.version = '9.1.0'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'
diff --git a/lib/medium/2181_merge_nodes_in_between_zeros.rb b/lib/medium/2181_merge_nodes_in_between_zeros.rb
new file mode 100644
index 00000000..996fd96d
--- /dev/null
+++ b/lib/medium/2181_merge_nodes_in_between_zeros.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/merge-nodes-in-between-zeros/
+# @param {ListNode} head
+# @return {ListNode}
+def merge_nodes2181(head)
+  r_p = head.next
+  p_p = head.next.next
+
+  while p_p.next
+    if p_p.val.zero?
+      r_p.next = p_p.next
+      r_p = r_p.next
+      p_p = p_p.next
+    else
+      r_p.val += p_p.val
+    end
+
+    p_p = p_p.next
+  end
+
+  r_p.val += p_p.val
+  r_p.next = nil
+
+  head.next
+end
diff --git a/test/medium/test_2181_merge_nodes_in_between_zeros.rb b/test/medium/test_2181_merge_nodes_in_between_zeros.rb
new file mode 100644
index 00000000..461f12d2
--- /dev/null
+++ b/test/medium/test_2181_merge_nodes_in_between_zeros.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/common/linked_list'
+require_relative '../../lib/medium/2181_merge_nodes_in_between_zeros'
+require 'minitest/autorun'
+
+class MergeNodesInBetweenZerosTest < ::Minitest::Test
+  def test_default_one
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [4, 11]
+        ),
+        merge_nodes2181(
+          ::ListNode.from_array(
+            [0, 3, 1, 0, 4, 5, 2, 0]
+          )
+        )
+      )
+    )
+  end
+
+  def test_default_two
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [1, 3, 4]
+        ),
+        merge_nodes2181(
+          ::ListNode.from_array(
+            [0, 1, 0, 3, 0, 2, 2, 0]
+          )
+        )
+      )
+    )
+  end
+end