diff --git a/README.md b/README.md
index 305c8595..9c92dca6 100644
--- a/README.md
+++ b/README.md
@@ -583,3 +583,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 462. Minimum Moves to Equal Array Elements II                   | [Link](https://leetcode.com/problems/minimum-moves-to-equal-array-elements-ii/)                   | [Link](./lib/medium/462_minimum_moves_to_equal_array_elements_ii.rb)                   | [Link](./test/medium/test_462_minimum_moves_to_equal_array_elements_ii.rb)                   |
 | 468. Validate IP Address                                        | [Link](https://leetcode.com/problems/validate-ip-address/)                                        | [Link](./lib/medium/468_validate_ip_address.rb)                                        | [Link](./test/medium/test_468_validate_ip_address.rb)                                        |
 | 474. Ones and Zeroes                                            | [Link](https://leetcode.com/problems/ones-and-zeroes/)                                            | [Link](./lib/medium/474_ones_and_zeroes.rb)                                            | [Link](./test/medium/test_474_ones_and_zeroes.rb)                                            |
+| 503. Next Greater Element II                                    | [Link](https://leetcode.com/problems/next-greater-element-ii/)                                    | [Link](./lib/medium/503_next_greater_element_ii.rb)                                    | [Link](./test/medium/test_503_next_greater_element_ii.rb)                                    |
diff --git a/leetcode-ruby.gemspec b/leetcode-ruby.gemspec
index ea9cfc32..53be4232 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 = '7.1.7'
+  s.version = '7.1.8'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'
diff --git a/lib/medium/503_next_greater_element_ii.rb b/lib/medium/503_next_greater_element_ii.rb
new file mode 100644
index 00000000..9dbd4d09
--- /dev/null
+++ b/lib/medium/503_next_greater_element_ii.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/next-greater-element-ii/
+# @param {Integer[]} nums
+# @return {Integer[]}
+def next_greater_elements(nums)
+  result = []
+  stack = []
+  (0...(2 * nums.size)).reverse_each do |i|
+    index = i % nums.size
+
+    stack.pop while !stack.empty? && nums[stack.last] <= nums[index]
+
+    result[index] = stack.empty? ? -1 : nums[stack.last]
+    stack << index
+  end
+
+  result
+end
diff --git a/test/medium/test_503_next_greater_element_ii.rb b/test/medium/test_503_next_greater_element_ii.rb
new file mode 100644
index 00000000..31df6e45
--- /dev/null
+++ b/test/medium/test_503_next_greater_element_ii.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/503_next_greater_element_ii'
+require 'minitest/autorun'
+
+class NextGreaterElementIITest < ::Minitest::Test
+  def test_default_one
+    assert_equal(
+      [2, -1, 2],
+      next_greater_elements(
+        [1, 2, 1]
+      )
+    )
+  end
+
+  def test_default_two
+    assert_equal(
+      [2, 3, 4, -1, 4],
+      next_greater_elements(
+        [1, 2, 3, 4, 3]
+      )
+    )
+  end
+end