Jesse Pope - Maple CS Fun

hash_practice/exercises.py

@@ -1,19 +1,50 @@
+def sort_string(string):
+    sorted_chars = sorted(string)
+    sorted_string = "".join(sorted_chars)
+
+    return sorted_string
+
 
 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
+    arrays = {}
+    for string in strings:
+        sorted = sort_string(string)
+        if sorted in arrays:
+            arrays[sorted].append(string)
+        else:
+            arrays[sorted] = [string]
+
+    groups = [group for group in arrays.values()]
+
+    return groups
+
 
 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(nlogn)
+        Space Complexity: O(n)
     """
-    pass
+    if not nums:
+        return []
+
+    freq_map = {}
+    for e in nums:
+        if e in freq_map:
+            freq_map[e] +=1
+        else:
+            freq_map[e] = 1
+
+    sorted_nums = sorted(freq_map.items(), key=lambda map_key: map_key[1], reverse=True)
+
+    common_nums = [e[0] for e in sorted_nums]
+
+    return common_nums[:k]
 
 
 def valid_sudoku(table):