More solutions. Ruby makes it easy

Author: James Zhang

factorial/factorial.rb

@@ -0,0 +1,4 @@
+def factorial(n)
+  return 1 if n < 2
+  n * factorial(n - 1)
+end

multiples-of-3-and-5/multiples_of_three_and_five.rb

@@ -0,0 +1,3 @@
+def multiples_of_three_and_five
+  (1...1000).to_a.select { |num| num % 3 == 0 || num % 5 == 0 }.reduce(&:+)
+end

odd-occuring-element/odd_occuring_element.rb

@@ -0,0 +1,5 @@
+def odd_occuring_element(array)
+  array.uniq.each do |num|
+    return num if array.count(num) % 2 != 0
+  end
+end

remove-duplicates-from-string/remove_duplicates.rb

@@ -0,0 +1,3 @@
+def remove_duplicates(str)
+  str.split("").uniq.join
+end

reverse-words-in-string/reverse_words.rb

@@ -0,0 +1,3 @@
+def reverse_words(array)
+  array.split(" ").reverse.join(" ")
+end