From d6184428bef17ff871a0963f30b3a61a8e5eacea Mon Sep 17 00:00:00 2001
From: peachmakkoli <lee.higgins.dev@gmail.com>
Date: Tue, 6 Oct 2020 20:19:56 -0700
Subject: [PATCH 1/2] completes newman_conway method

---
 lib/newman_conway.rb | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/lib/newman_conway.rb b/lib/newman_conway.rb
index 4c985cd..6b875c3 100644
--- a/lib/newman_conway.rb
+++ b/lib/newman_conway.rb
@@ -1,7 +1,21 @@
 
 
-# Time complexity: ?
-# Space Complexity: ?
+# Time complexity: O(n) if num is greater than 2, where n is num 
+# Space Complexity: O(n)
 def newman_conway(num)
-  raise NotImplementedError, "newman_conway isn't implemented"
-end
\ No newline at end of file
+  raise ArgumentError if num < 1
+  sequence = [0, 1, 1]
+  output = ""
+  output += "#{sequence[1]}" + " "
+  output += "#{sequence[2]}" + " " if num > 1
+
+  i = 3
+  while i <= num
+    sequence << sequence[sequence[i - 1]] + sequence[i - sequence[i - 1]]
+    output += "#{sequence[i]}" + " "
+    i += 1
+  end
+
+  return output.chomp(" ")
+end
+        
\ No newline at end of file

From f403eef8baf966b2b6f44a0819fed7e925f44c57 Mon Sep 17 00:00:00 2001
From: peachmakkoli <lee.higgins.dev@gmail.com>
Date: Tue, 6 Oct 2020 20:36:05 -0700
Subject: [PATCH 2/2] completes max_sub_array

---
 lib/max_subarray.rb        | 18 +++++++++++++-----
 lib/newman_conway.rb       |  2 +-
 test/max_sub_array_test.rb |  2 +-
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/lib/max_subarray.rb b/lib/max_subarray.rb
index 5204edb..b9f7f83 100644
--- a/lib/max_subarray.rb
+++ b/lib/max_subarray.rb
@@ -1,8 +1,16 @@
+# Reference: https://medium.com/@rsinghal757/kadanes-algorithm-dynamic-programming-how-and-why-does-it-work-3fd8849ed73d
 
-# Time Complexity: ?
-# Space Complexity: ?
+# Time Complexity: O(n), where n is the length of nums
+# Space Complexity: O(1)
 def max_sub_array(nums)
-    return 0 if nums == nil
-    
-    raise NotImplementedError, "Method not implemented yet!"
+  max = nums[0]
+  local_max = 0
+
+  nums.each do |n|
+    local_max += n
+    max = local_max if max < local_max
+    local_max = 0 if local_max < 0
+  end
+
+  return max
 end
diff --git a/lib/newman_conway.rb b/lib/newman_conway.rb
index 6b875c3..d52c243 100644
--- a/lib/newman_conway.rb
+++ b/lib/newman_conway.rb
@@ -1,4 +1,4 @@
-
+# Reference: https://www.geeksforgeeks.org/print-n-terms-newman-conway-sequence/
 
 # Time complexity: O(n) if num is greater than 2, where n is num 
 # Space Complexity: O(n)
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]