space - Nora

lib/array_intersection.rb

@@ -1,3 +1,18 @@
 def intersection(list1, list2)
-  raise NotImplementedError, "Intersection not implemented"
+  hash = {}
+  intersect = []
+
+  list1.each do |item|
+    hash[item] = true
+  end
+
+  list2.each do |item|
+    if hash[item]
+      intersect << item
+    end
+  end
+
+  return intersect
+
+
 end

lib/palindrome_permutation.rb

@@ -1,4 +1,24 @@
-
 def palindrome_permutation?(string)
-  raise NotImplementedError, "palindrome_permutation? not implemented"
-end
+  if string.empty?
+    return true
+  end
+
+  hash = {}
+  array = string.chars
+
+  array.each do |char|
+    if hash[char]
+      hash[char] += 1
+    else
+      hash[char] = 1
+    end
+  end
+
+  odd = 0
+
+  hash.each do |key, value|
+    odd += 1 if value % 2 != 0
+  end
+
+  odd > 1 ? false : true
+end

lib/permutations.rb

@@ -1,4 +1,23 @@
 
 def permutations?(string1, string2)
-  raise NotImplementedError, "permutations? not implemented"
+
+  return true if string1.empty? || string2.empty?
+  return false if string1.length != string2.length
+
+  array1 = string1.chars
+  array2 = string2.chars
+
+  hash = {}
+
+  array1.each do |char|
+    hash[char] = true
+  end
+
+  array2.each do |char|
+    if hash[char] == nil
+      return false
+    end
+  end
+
+  return true
 end

test/palindrome_permutation_test.rb

@@ -1,6 +1,6 @@
 require_relative "test_helper"
 
-xdescribe "palindrome_permutation?" do
+describe "palindrome_permutation?" do
   it "will work for hello" do
     expect(palindrome_permutation?("hello")).must_equal false
   end
@@ -19,5 +19,5 @@
 
   it "will return false for raceca" do
     expect(palindrome_permutation?("raceca")).must_equal false
-  end   
-end
+  end
+end

test/permutations_test.rb

@@ -1,6 +1,6 @@
 require_relative "test_helper"
 
-xdescribe "permutations?" do
+describe "permutations?" do
   it "returns true for empty string" do
     expect(permutations?("", "")).must_equal true
   end