Water - Sophia

Gemfile.lock

@@ -0,0 +1,36 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ansi (1.5.0)
+    builder (3.2.4)
+    coderay (1.1.3)
+    method_source (1.0.0)
+    minitest (5.14.2)
+    minitest-reporters (1.4.2)
+      ansi
+      builder
+      minitest (>= 5.0)
+      ruby-progressbar
+    minitest-skip (0.0.3)
+      minitest (~> 5.0)
+    minitest-spec (0.0.2.1)
+      minitest (>= 3.0)
+    pry (0.13.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    rake (13.0.1)
+    ruby-progressbar (1.10.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  minitest
+  minitest-reporters
+  minitest-skip
+  minitest-spec
+  pry
+  rake
+
+BUNDLED WITH
+   2.1.4

lib/recursive-methods.rb

@@ -1,49 +1,88 @@
 # 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"
+    if n == 0
+        return 1
+    elsif n < 0
+        raise ArgumentError
+    else
+        return n * factorial(n-1)
+    end
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(n)
 def reverse(s)
-    raise NotImplementedError, "Method not implemented"
+    if s.length <= 1
+        return s
+    else
+        return reverse(s[1..-1]) + s[0]
+    end
 end
 
-# Time complexity: ?
-# Space complexity: ?
+# # Time complexity: O(1)
+# # Space complexity: O(1)
 def reverse_inplace(s)
-    raise NotImplementedError, "Method not implemented"
+    if s.length <= 1
+        return s
+    else
+        return s.reverse!
+    end
 end
-
-# Time complexity: ?
-# Space complexity: ?
+#
+# # Time complexity: O(n)
+# # Space complexity: O(n)
 def bunny(n)
-    raise NotImplementedError, "Method not implemented"
+    if n == 0
+        return 0
+    else
+        return 2 + bunny(n-1)
+    end
 end
-
-# Time complexity: ?
-# Space complexity: ?
+#
+# # Time complexity: O(n^2) * not sure about this one
+# # Space complexity: O(n^2) * same here?
 def nested(s)
-    raise NotImplementedError, "Method not implemented"
+    if s == ""
+        return true
+    elsif
+    s[0] == "(" && s[-1] == ")"
+        return nested(s[1..-2])
+    else
+        return false
+    end
 end
-
-# Time complexity: ?
-# Space complexity: ?
+#
+# # Time complexity: O(n)
+# # Space complexity: O(n^2)
 def search(array, value)
-    raise NotImplementedError, "Method not implemented"
+    if array.nil?
+        return false
+    elsif
+    array[0] == value
+        return true
+    else
+        return search(array[1..-1], value)
+    end
 end
-
-# Time complexity: ?
-# Space complexity: ?
+#
+# # Time complexity: O(n)
+# # Space complexity: O(n)
 def is_palindrome(s)
-    raise NotImplementedError, "Method not implemented"
+    if s.length <= 1
+        return true
+    elsif s[0] != s[-1]
+        return false
+    else
+        return is_palindrome(s[1..-2])
+    end
 end
-
-# Time complexity: ?
-# Space complexity: ?
+#
+# # Time complexity: ?
+# # Space complexity: ?
 def digit_match(n, m)
-    raise NotImplementedError, "Method not implemented"
-end
+    #Not sure how to get started on this one.
+end
+

test/recursion_writing_test.rb

@@ -167,7 +167,7 @@
   end
 end
 
-xdescribe "nested" do
+describe "nested" do
   it "will return true for empystring" do
     # Arrange
     string = ""
@@ -213,7 +213,7 @@
   end
 end
 
-xdescribe "search" do
+describe "search" do
   it "will return false for empty array" do
     # Arrange
     item = "a"
@@ -263,7 +263,7 @@
     end      
 end
 
-xdescribe "is_palindrome" do
+describe "is_palindrome" do
   it "will return true for emptystring" do
     # Arrange
     string = ""