passing tests

lib/reverse_sentence.rb

@@ -1,4 +1,61 @@
-# A method to reverse the words in a sentence, in place.
-def reverse_sentence(my_sentence)
-  raise NotImplementedError
+require 'pry'
+
+def word_reverse(my_string, right_index, left_index)
+
+  return if (my_string == nil || my_string.length == 0 )
+  return my_string if (left_index == right_index)
+
+  right = right_index
+  left = left_index
+  while right < left
+    left_container = my_string[left]
+    my_string[left] = my_string[right]
+    my_string[right] = left_container
+    right += 1
+    left -= 1
+  end
+  return my_string
+end
+
+def reverse_words(my_words)
+
+  return if (my_words == nil || my_words.length == 0)
+
+  right_index = 0
+  left_index = 0
+
+  while left_index < my_words.length
+
+    while my_words[right_index] == ' ' && right_index < my_words.length
+      right_index += 1
+    end
+
+    left_index = right_index + 1
+
+    while my_words[left_index]!= ' ' && left_index < my_words.length
+      left_index += 1
+    end
+
+    left_index -= 1
+
+    word_reverse(my_words, right_index, left_index)
+
+    right_index = left_index + 1
+  end
+
+  return my_words
+
+end
+
+def reverse_sentence(sentence)
+
+  return if sentence == nil || sentence.length < 2
+
+  right_index = 0
+  left_index = sentence.length - 1
+
+  word_reverse(sentence, right_index, left_index)
+
+  reverse_words(sentence)
+
 end