diff --git a/lib/recursive-methods.rb b/lib/recursive-methods.rb
index fbf6faa..673b77b 100644
--- a/lib/recursive-methods.rb
+++ b/lib/recursive-methods.rb
@@ -1,49 +1,87 @@
 # Authoring recursive algorithms. Add comments including time and space complexity for each method.
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(n)
 def factorial(n)
-    raise NotImplementedError, "Method not implemented"
+  raise ArgumentError if n < 0
+  
+  return 1 if n <= 1
+  return n * factorial(n-1)
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(s.length) or O(n)
+# Space complexity: O(s.length) or O(n)
 def reverse(s)
-    raise NotImplementedError, "Method not implemented"
+  return s if s.length <= 1
+  
+  return s[s.length-1] << reverse(s[1..-2]) << s[0]
 end
 
 # Time complexity: ?
-# Space complexity: ?
+# Space complexity: O(1)
 def reverse_inplace(s)
-    raise NotImplementedError, "Method not implemented"
+  # How would I do this??
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(n)
 def bunny(n)
-    raise NotImplementedError, "Method not implemented"
+  return 0 if n == 0
+  
+  return 2 + bunny(n-1)
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(s.length) or O(n)
+# Space complexity: O(1)
 def nested(s)
-    raise NotImplementedError, "Method not implemented"
+  return true if s.nil?
+  return false if s.length == 1
+  
+  if s.length == 2
+    if s == "()"
+      return true
+    else
+      return false
+    end
+  end
+  
+  nested(s[1..-2])
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(array.length) or O(n)
+# Space complexity: O(1)
 def search(array, value)
-    raise NotImplementedError, "Method not implemented"
+  return false if array.length == 0
+  
+  return true if array[0] == value
+  
+  search(array[1..-1], value)
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(s.length) or O(n)
+# Space complexity: O(1)
 def is_palindrome(s)
-    raise NotImplementedError, "Method not implemented"
+  return true if s.length <= 1
+  
+  return false if s[0] != s[-1]
+  
+  is_palindrome(s[1..-2])
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(log(n)) or O(log(m)) whichever is shorter
+# Space complexity: O(log(n)) or O(log(m)) whichever is shorter
 def digit_match(n, m)
-    raise NotImplementedError, "Method not implemented"
-end
\ No newline at end of file
+  if (n % 10) == (m % 10)
+    if n < 10 || m < 10
+      return 1
+    else
+      return 1 + digit_match(n/10, m/10)
+    end
+  else
+    if n < 10 || m < 10
+      return 0
+    else
+      return 0 + digit_match(n/10, m/10)
+    end
+  end
+end
diff --git a/test/recursion_writing_test.rb b/test/recursion_writing_test.rb
index 820810e..4527714 100644
--- a/test/recursion_writing_test.rb
+++ b/test/recursion_writing_test.rb
@@ -7,77 +7,77 @@
   it "will find the factorial of 0" do
     # Arrange
     num = 0
-
+    
     # Act
     answer = factorial(num)
-
+    
     # Assert
     expect(answer).must_equal 1
   end
-
+  
   it "will find the factorial of 5" do
     # Arrange
     num = 5
-
+    
     # Act
     answer = factorial(num)
-
+    
     # Assert
     expect(answer).must_equal 5*4*3*2*1
-
+    
   end
-
+  
   it "will raise an ArgumentError if given a number not >= 0" do
     # Arrange
     num = -1
-
+    
     # Act-Assert
     expect {
-      answer = factorial(num)
-    }.must_raise ArgumentError
-  end
+    answer = factorial(num)
+  }.must_raise ArgumentError
+end
 end
 
-xdescribe "reverse" do
+describe "reverse" do
   it "will reverse 'cat'" do
     # Arrange
     string = "cat"
-
+    
     # Act
     answer = reverse(string)
-
+    
     # Assert
     expect(answer).must_equal "tac"
   end
-
+  
   it "will reverse 'a'" do
     # Arrange
     string = "a"
-
+    
     # Act
     answer = reverse(string)
-
+    
     # Assert
     expect(answer).must_equal "a"
   end
-
+  
   it "will reverse empty string " do
     # Arrange
     string = ""
-
+    
     # Act
     answer = reverse(string)
-
+    
     # Assert
     expect(answer).must_equal ""
   end
   it "will reverse 'apple'" do
     # Arrange
     string = "apple"
-
+    
     # Act
     answer = reverse(string)
-
+    
     # Assert
     expect(answer).must_equal "elppa"
   end
@@ -88,208 +88,208 @@
   it "will reverse 'cat'" do
     # Arrange
     string = "cat"
-
+    
     # Act
     answer = reverse_inplace(string)
-
+    
     # Assert
     expect(answer).must_equal "tac"
   end
-
+  
   it "will reverse 'a'" do
     # Arrange
     string = "a"
-
+    
     # Act
     answer = reverse_inplace(string)
-
+    
     # Assert
     expect(answer).must_equal "a"
   end
-
+  
   it "will reverse empty string " do
     # Arrange
     string = ""
-
+    
     # Act
     answer = reverse_inplace(string)
-
+    
     # Assert
     expect(answer).must_equal ""
   end
   it "will reverse 'apple'" do
     # Arrange
     string = "apple"
-
+    
     # Act
     answer = reverse_inplace(string)
-
+    
     # Assert
     expect(answer).must_equal "elppa"
   end
 end
 
-xdescribe "bunny" do
+describe "bunny" do
   it "returns 0 for 0 bunnies" do
     # Arrange
     count = 0
-
+    
     # Act
     answer = bunny(count)
-
+    
     # Assert
     expect(answer).must_equal 0
   end
-
+  
   it "returns 2 for 1 bunny" do
     # Arrange
     count = 1
-
+    
     # Act
     answer = bunny(count)
-
+    
     # Assert
     expect(answer).must_equal 2
   end
-
+  
   it "returns 100 for 50 bunnies" do
     # Arrange
     count = 50
-
+    
     # Act
     answer = bunny(count)
-
+    
     # Assert
     expect(answer).must_equal 100
   end
 end
 
-xdescribe "nested" do
+describe "nested" do
   it "will return true for empystring" do
     # Arrange
     string = ""
-
+    
     # Act
     answer = nested(string)
-
+    
     # Assert
     expect(answer).must_equal true
   end
-
+  
   it "will return true for a nested series of parens" do
     # Arrange
     string = "((()))"
-
+    
     # Act
     answer = nested(string)
-
+    
     # Assert
     expect(answer).must_equal true
   end
-
+  
   it "will return false for a nested series of parens" do
     # Arrange
     string = "(()))"
-
+    
     # Act
     answer = nested(string)
-
+    
     # Assert
     expect(answer).must_equal false
   end
-
+  
   it "will return false for an even length improperly nested series of parens" do
     # Arrange
     string = "(())))"
-
+    
     # Act
     answer = nested(string)
-
+    
     # Assert
     expect(answer).must_equal false
   end
 end
 
-xdescribe "search" do
+describe "search" do
   it "will return false for empty array" do
     # Arrange
     item = "a"
     array = []
-
+    
     # Act
     answer = search(array, item)
-
+    
     # Assert
     expect(answer).must_equal false
   end
-
+  
   it "will return true when looking for something in the array" do
-  # Arrange
-  item = "a"
-  array = ["b", "c", "a"]
-
-  # Act
-  answer = search(array, item)
-
-  # Assert
-  expect(answer).must_equal true
+    # Arrange
+    item = "a"
+    array = ["b", "c", "a"]
+    
+    # Act
+    answer = search(array, item)
+    
+    # Assert
+    expect(answer).must_equal true
   end
-
+  
   it "will return false when looking for something not in the array" do
     # Arrange
     item = "x"
     array = ["b", "c", "a"]
-  
+    
     # Act
     answer = search(array, item)
-  
+    
     # Assert
     expect(answer).must_equal false
-    end
-
-    it "will return true when finding something at the front of the array" do
-      # Arrange
-      item = "b"
-      array = ["b", "c", "a"]
+  end
+  
+  it "will return true when finding something at the front of the array" do
+    # Arrange
+    item = "b"
+    array = ["b", "c", "a"]
     
-      # Act
-      answer = search(array, item)
+    # Act
+    answer = search(array, item)
     
-      # Assert
-      expect(answer).must_equal true
-    end      
+    # Assert
+    expect(answer).must_equal true
+  end      
 end
 
-xdescribe "is_palindrome" do
+describe "is_palindrome" do
   it "will return true for emptystring" do
     # Arrange
     string = ""
-
+    
     # Act
     answer = is_palindrome(string)
-
+    
     # Assert
     expect(answer).must_equal true
   end
-
+  
   it "will return true for a palindrome" do
     # Arrange
     string = "racecar"
-
+    
     # Act
     answer = is_palindrome(string)
-
+    
     # Assert
     expect(answer).must_equal true
   end
-
+  
   it "will return false for a nonpalindrome" do
     # Arrange
     string = "raecar"
-
+    
     # Act
     answer = is_palindrome(string)
-
+    
     # Assert
     expect(answer).must_equal false
   end
@@ -300,59 +300,59 @@
     # Arrange
     num1 = 1072503891
     num2 = 62530841
-
+    
     # Act
     answer = digit_match(num1, num2)
-
-     # Assert
-     expect(answer).must_equal 4
+    
+    # Assert
+    expect(answer).must_equal 4
   end
-
+  
   it "returns 0 for nonmatching numbers" do
     # Arrange
     num1 = 0
     num2 = 62530841
-
+    
     # Act
     answer = digit_match(num1, num2)
-
-     # Assert
-     expect(answer).must_equal 0
+    
+    # Assert
+    expect(answer).must_equal 0
   end
-
+  
   it "returns 3 for 841 and 62530841" do
     # Arrange
     num1 = 841
     num2 = 62530841
-
+    
     # Act
     answer = digit_match(num1, num2)
-
-     # Assert
-     expect(answer).must_equal 3
+    
+    # Assert
+    expect(answer).must_equal 3
   end
   
   it "returns 1 for (0, 0)" do
     # Arrange
     num1 = 0
     num2 = 0
-
+    
     # Act
     answer = digit_match(num1, num2)
-
-     # Assert
-     expect(answer).must_equal 1
+    
+    # Assert
+    expect(answer).must_equal 1
   end
   
   it "returns 1 for (10, 20)" do
     # Arrange
     num1 = 10
     num2 = 20
-
+    
     # Act
     answer = digit_match(num1, num2)
-
-     # Assert
-     expect(answer).must_equal 1
+    
+    # Assert
+    expect(answer).must_equal 1
   end
 end