diff --git a/hash_practice/exercises.py b/hash_practice/exercises.py
index 48bf95e..57b1548 100644
--- a/hash_practice/exercises.py
+++ b/hash_practice/exercises.py
@@ -2,18 +2,35 @@
 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
+    anagrams_map = {}
+    for word in strings:
+        alpha_word = "".join(sorted(word))
+        if anagrams_map.get(alpha_word):
+            anagrams_map[alpha_word].append(word)
+        else:
+            anagrams_map[alpha_word]= [word]
+
+        
+    return list(anagrams_map.values())
 
 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)
+        Space Complexity: O(n)
     """
-    pass
+    nums_map = {}
+    
+    for num in nums:
+        if not nums_map.get(num):
+            nums_map[num] = 0
+        nums_map[num] += 1
+    
+    sorted_nums_map_keys = sorted(nums_map.keys(), key=nums_map.get, reverse = True )
+    return sorted_nums_map_keys[:k]
 
 
 def valid_sudoku(table):
@@ -25,5 +42,7 @@ def valid_sudoku(table):
         Time Complexity: ?
         Space Complexity: ?
     """
-    pass
+    is_valid_sodoku = False
+
+    return is_valid_sodoku