Diana - Pine

hash_practice/exercises.py

@@ -2,18 +2,43 @@
 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)
+        Space Complexity: O(n)
     """
-    pass
+    anagram_hash = {}
+    anagram_list = []
+
+    for string in strings:
+        sorted_string = "".join(sorted(string))
+
+        if anagram_hash.get(sorted_string):
+            anagram_hash[sorted_string].append(string)
+
+        else:
+            anagram_hash[sorted_string] = [string]
+
+    for string in anagram_hash.values():
+        anagram_list.append(string)
+    return anagram_list 
 
 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
+    frequency = {}
+    for num in nums:
+        if num not in frequency:
+            frequency[num] = 1
+        else:
+            frequency[num] += 1
+    sorted_hash = sorted(frequency.items(), key=lambda x:(x[1]), reverse=True)
+    most_common = []
+
+    for i in sorted_hash:
+        most_common.append(i[0])
+    return most_common[:k]
 
 
 def valid_sudoku(table):