Maria M. - Scissors

hash_practice/exercises.py

@@ -2,18 +2,46 @@
 def grouped_anagrams(strings):
     """ 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 log n)
+        Space Complexity: O(n)
     """
-    pass
+    anagram_dict = {}
+    for word in strings:
+        sorted_word = ''.join(sorted(word))
+        if (sorted_word in anagram_dict):
+            anagram_dict[sorted_word].append(word)
+        else:
+            anagram_dict[sorted_word] = [word]
+
+    anagrams_array = []
+    for words in anagram_dict.values():
+        anagrams_array.append(words)
+    return anagrams_array
 
 def top_k_frequent_elements(nums, k):
     """ This method will return the k most common elements
         In the case of a tie it will select the first occuring element.
-        Time Complexity: ?
-        Space Complexity: ?
+        Time Complexity: O(n log n)
+        Space Complexity: O(n)
     """
-    pass
+
+    final_result = []
+    if not nums:
+        return final_result
+
+    most_freq_nums = {}
+    for i in range(0, len(nums)):
+        if nums[i] in most_freq_nums:
+            most_freq_nums[nums[i]] += 1
+        else:
+            most_freq_nums[nums[i]] = 1
+
+    sorted_nums = sorted(most_freq_nums.items(), 
+        key=lambda tuple: tuple[1], reverse=True)
+
+    for j in range(0, k):
+        final_result.append(sorted_nums[j][0])
+    return final_result
 
 
 def valid_sudoku(table):