Added Python solution for 347. Top K Frequent Elements

Algorithms/Medium/347_TopKFrequentElements/Solution.py

@@ -0,0 +1,19 @@
+class Solution:
+    def topKFrequent(self, nums: List[int], k: int) -> List[int]:
+        freq_arr = [ [] for _ in range(len(nums))]
+        elem_freq_map = {}
+
+        for elem in nums: 
+            elem_freq_map[elem] = elem_freq_map.get(elem, 0) + 1
+
+        for elem, idx in elem_freq_map.items():
+            freq_arr[idx - 1].append(elem)
+
+        res = []
+
+        for i in range(len(freq_arr) - 1, -1, -1):
+            if freq_arr[i]: res.extend(freq_arr[i])
+            if len(res) == k:
+                return res
+
+        return