From 4fd29c2809eab82abae3c0cc2383e330525ae747 Mon Sep 17 00:00:00 2001
From: Sam <samcoll@Samanthas-MBP.localdomain>
Date: Sat, 4 Apr 2020 12:06:29 -0700
Subject: [PATCH 1/2] newman_conway all tests pass

---
 lib/newman_conway.rb | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/lib/newman_conway.rb b/lib/newman_conway.rb
index 4c985cd..73fffd2 100644
--- a/lib/newman_conway.rb
+++ b/lib/newman_conway.rb
@@ -1,7 +1,22 @@
+# Time complexity: O(n)
+# Space Complexity: O(n)
+def newman_conway(num)
+  raise ArgumentError if num < 1
+  return "1" if num == 1
+  
+  seq = [0, 1, 1]
+  i = 3
+  result = "1 1"
+  
+  until i >= num + 1
+    current = seq[seq[i-1]] + seq[i - (seq[i-1])]
+    seq << current
+    result += " #{current}"
+    i += 1
+  end
+  
+  return result
+end 
 
 
-# Time complexity: ?
-# Space Complexity: ?
-def newman_conway(num)
-  raise NotImplementedError, "newman_conway isn't implemented"
-end
\ No newline at end of file
+#pp newman_conway(13)

From d7b594896824a78b7e0af4b3d16d721ea307ebba Mon Sep 17 00:00:00 2001
From: Sam <samcoll@Samanthas-MBP.localdomain>
Date: Sat, 4 Apr 2020 12:20:10 -0700
Subject: [PATCH 2/2] max_subarray all tests pass

---
 lib/max_subarray.rb        | 31 +++++++++++++++++++----
 test/max_sub_array_test.rb | 52 +++++++++++++++++++-------------------
 2 files changed, 52 insertions(+), 31 deletions(-)

diff --git a/lib/max_subarray.rb b/lib/max_subarray.rb
index 5204edb..04e2e03 100644
--- a/lib/max_subarray.rb
+++ b/lib/max_subarray.rb
@@ -1,8 +1,29 @@
-
-# Time Complexity: ?
-# Space Complexity: ?
+# Time Complexity: O(n)
+# Space Complexity: O(1)
 def max_sub_array(nums)
-    return 0 if nums == nil
+  return 0 if nums == nil
+  return nil if nums.empty?
+  
+  max = nums[0]
+  current_sum = 0
+  
+  i = 0
+  while i < nums.length
+    current_sum += nums[i]
+    
+    if current_sum > max
+      max = current_sum
+    end
+    
+    if current_sum < 0
+      current_sum = 0
+    end 
     
-    raise NotImplementedError, "Method not implemented yet!"
+    i += 1
+  end
+  
+  return max
 end
+
+
+#pp max_sub_array([-2,1,-3,4,-1,2,1,-5,4])
diff --git a/test/max_sub_array_test.rb b/test/max_sub_array_test.rb
index 3253cdf..fa2fed2 100644
--- a/test/max_sub_array_test.rb
+++ b/test/max_sub_array_test.rb
@@ -1,70 +1,70 @@
 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]
-
+    
     # Act
     answer = max_sub_array(input)
-
+    
     # Assert
     expect(answer).must_equal 6
   end
-
+  
   it "will work with a totally negative array" do
     # Arrange
     input = [-3, -4, -5, -6, -7]
-
+    
     # Act
     answer = max_sub_array(input)
-
+    
     # Assert
     expect(answer).must_equal(-3)
   end
-
+  
   it "will work with a totally negative array with the largest element at the rear" do
     # Arrange
     input = [ -4, -5, -6, -7, -3]
-
+    
     # Act
     answer = max_sub_array(input)
-
+    
     # Assert
     expect(answer).must_equal(-3)
   end
-
+  
   it "will work with a 1-element array" do
     # Arrange
     input = [3]
-
+    
     # Act
     answer = max_sub_array(input)
-
+    
     # Assert
     expect(answer).must_equal 3
   end
-
+  
   it "will return nil for an empty array" do
-   # Arrange
-   input = []
-
-   # Act
-   answer = max_sub_array(input)
-
-   # Assert
-   expect(answer).must_be_nil
+    # Arrange
+    input = []
+    
+    # Act
+    answer = max_sub_array(input)
+    
+    # Assert
+    expect(answer).must_be_nil
   end
-
+  
   it "will work for [50, -50, 50]" do
     # Arrange
     input = [50, -50, 50]
-
+    
     # Act
     answer = max_sub_array(input)
-
+    
     # Assert
     expect(answer).must_equal 50
   end
-
-end
\ No newline at end of file
+  
+end