Erica

lib/exercises.rb

@@ -2,11 +2,35 @@
 
 # This method will return an array of arrays.
 # Each subarray will have strings which are anagrams of each other
-# Time Complexity: ?
-# Space Complexity: ?
+# Time Complexity: O(n), where n is the number of words in strings, for the each loop
+# I'm not sure what the time complexity is for string.chars.sort.join, but I would guess 
+# O(m), where m is the number of letters in strings 
+# if I am correct, that would be O(m*n) total
+# If the words are as short as they are in the tests, we can assume that m is minimal enough
+# for it to be nearly constant, resulting in a O(n) total.
+
+# Space Complexity: O(n), where n is the number of words in strings
 
 def grouped_anagrams(strings)
-  raise NotImplementedError, "Method hasn't been implemented yet!"
+  return [] if strings.length == 0
+
+  result = []
+  hash = {}
+  count = 0
+
+  strings.each do |string|
+    sorted_string = string.chars.sort.join
+
+    if hash[sorted_string] 
+      result[hash[sorted_string]].push(string)
+    else
+      hash[sorted_string] = count
+      result.push([string])
+      count += 1
+    end
+  end
+
+  return result
 end
 
 # This method will return the k most common elements