diff --git a/lib/max_subarray.rb b/lib/max_subarray.rb
index 5204edb..bbb9566 100644
--- a/lib/max_subarray.rb
+++ b/lib/max_subarray.rb
@@ -2,7 +2,25 @@
 # Time Complexity: ?
 # Space Complexity: ?
 def max_sub_array(nums)
-    return 0 if nums == nil
+  return nil if (nums == nil || nums.length === 0)
+  
+  max = nums[0]
+  temp = 0 
+  
+  nums.each do |num|
+    temp += num
     
-    raise NotImplementedError, "Method not implemented yet!"
+    if temp > max
+      max = temp
+    end  
+    
+    if temp < 0
+      temp = 0
+    end
+  end
+  
+  return max
 end
+
+
+# p max_sub_array([-2,1,-3,4,-1,2,1,-5,4])
\ No newline at end of file
diff --git a/lib/newman_conway.rb b/lib/newman_conway.rb
index 4c985cd..db79e8a 100644
--- a/lib/newman_conway.rb
+++ b/lib/newman_conway.rb
@@ -1,7 +1,23 @@
+# Time complexity: O(n)
+# Space Complexity: O(n)
+def newman_conway(num)
+  return nc_helper(num)
+end
 
+def nc_helper(num, count = 2, memo = [0, 1, 1], result = "1 1")
+  raise ArgumentError if num <= 0
+  return "1" if num == 1
+  return "1 1" if num == 2
+  
+  if count == num
+    return result
+  end
+  
+  value = memo[memo[count]] + memo[count + 1 - memo[count]]
+  memo << value
+  result << " #{value}"
+  
+  return nc_helper(num, count + 1, memo, result)
+end
 
-# Time complexity: ?
-# Space Complexity: ?
-def newman_conway(num)
-  raise NotImplementedError, "newman_conway isn't implemented"
-end
\ No newline at end of file
+# p newman_conway(12)
\ No newline at end of file