diff --git a/lib/max_subarray.rb b/lib/max_subarray.rb
index 5204edb..527fc4e 100644
--- a/lib/max_subarray.rb
+++ b/lib/max_subarray.rb
@@ -1,8 +1,16 @@
 
-# Time Complexity: ?
-# Space Complexity: ?
+# Time Complexity: O(nlogn)
+# Space Complexity: O(n)
 def max_sub_array(nums)
-    return 0 if nums == nil
-    
-    raise NotImplementedError, "Method not implemented yet!"
+    local_max = 0
+    max = nil
+    i = 0
+    until i == nums.length
+        local_max = [nums[i], nums[i] + local_max].max
+        if max == nil || max < local_max
+            max = local_max
+        end
+        i += 1
+    end
+    return max
 end
diff --git a/lib/newman_conway.rb b/lib/newman_conway.rb
index 4c985cd..44a0250 100644
--- a/lib/newman_conway.rb
+++ b/lib/newman_conway.rb
@@ -1,7 +1,18 @@
 
 
-# Time complexity: ?
-# Space Complexity: ?
+# Time complexity: O(n)
+# Space Complexity: O(n)
 def newman_conway(num)
-  raise NotImplementedError, "newman_conway isn't implemented"
+  raise ArgumentError.new('num must be greater than 0') if num == 0
+  return '1' if num == 1
+  array = []
+  array[0] = 0
+  array[1], array[2] = 1, 1
+  i = 3
+  while i <= num
+    array[i] = array[array[i-1]] + array[i - array[i - 1]]
+    i += 1
+  end
+  array.slice!(0)
+  return array.join(',').gsub(',', ' ')
 end
\ No newline at end of file
diff --git a/test/max_sub_array_test.rb b/test/max_sub_array_test.rb
index 3253cdf..e27e1ca 100644
--- a/test/max_sub_array_test.rb
+++ b/test/max_sub_array_test.rb
@@ -1,6 +1,6 @@
 require_relative "test_helper"
 
-xdescribe "max subarray" do
+describe "max subarray" do
   it "will work for [-2,1,-3,4,-1,2,1,-5,4]" do
     # Arrange
     input = [-2,1,-3,4,-1,2,1,-5,4]