diff --git a/lib/max_subarray.rb b/lib/max_subarray.rb index 5204edb..46e863a 100644 --- a/lib/max_subarray.rb +++ b/lib/max_subarray.rb @@ -1,8 +1,19 @@ -# 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 - raise NotImplementedError, "Method not implemented yet!" + max_sum = nums[0] + max_ending_here = nums[0] + + i = 1 + while i < nums.length + max_ending_here = max_ending_here + nums[i] + max_ending_here = [max_ending_here, nums[i]].max + max_sum = [max_sum, max_ending_here].max + i += 1 + end + + return max_sum end diff --git a/lib/newman_conway.rb b/lib/newman_conway.rb index 4c985cd..2626e9a 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 if num <= 0 + return "1" if num == 1 + return "1 1" if num == 2 + + array = [0, 1, 1] + i = 3 + while i <= num + array[i] = array[array[i - 1]] + array[i - array[i - 1]] + i += 1 + end + + return array[1..-1].join(" ") 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]