Daniela - Leaves

lib/fibonacci.rb

@@ -1,8 +1,20 @@
 # Improved Fibonacci
 
-# Time Complexity - ?
+# Time Complexity - O(n)
 # Space Complexity - ?  (should be O(n))
 # Hint, you may want a recursive helper method
 def fibonacci(n)
-
+  return fib_helper( [0,1], 2, n )
+end
+
+def fib_helper( solutions, current, n )
+  return n if n == 0 || n == 1
+  raise ArgumentError if n < 0
+
+  if current == n
+    return solutions[n - 1] + solutions[n - 2]
+  end
+
+  solutions << solutions[current - 1] + solutions[current -2]
+  return fib_helper(solutions, current + 1, n)
 end

lib/super_digit.rb

@@ -1,15 +1,42 @@
 # Superdigit
 
-# Time Complexity - ?
-# Space Complexity - ?
+# Time Complexity : O(n), depends on number of digits 
+# Space Complexity : O(1) as the array of digits will always be same and I will always have same variables (sum, reminder)
 def super_digit(n)
-
+
+  return n if [0,1,2,3,4,5,6,7,8,9].include?(n) == true
+
+  sum = 0
+  until n == 0 do
+    reminder = n % 10
+    sum += reminder
+    n = n/10
+  end
+
+  super_digit(sum) 
 end
 
 
-# Time Complexity - ?
-# Space Complexity - ?
+# Time Complexity - O(n), depends on number of digits 
+# Space Complexity : O(1) as the array of digits will always be same and I will always have same variables (sum, reminder, superdigit)
 def refined_super_digit(n, k)
-
+
+  return n  if [0,1,2,3,4,5,6,7,8,9].include?(n) == true && k == 1
+
+  sum = 0
+  until n == 0 do
+    reminder = n % 10
+    sum += reminder
+    n = n/10
+  end
+
+  redifined_number = sum * k
+  refined_super_digit(redifined_number, 1)
 end
-
+
+
+
+
+
+
+

test/super_digit_test.rb

@@ -1,6 +1,6 @@
 require_relative "test_helper"
 
-xdescribe "super_digit" do
+describe "super_digit" do
   it "will return 2 for super_digit(9875)" do
     # Act
     answer = super_digit(9875)