Merge pull request #320 from mangodm-web/main

[DM] Week 01 Solutions

Author: mangodm-web

contains-duplicate/dm.py

@@ -0,0 +1,6 @@
+from typing import List
+
+
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        return len(nums) != len(set(nums))

number-of-1-bits/dm.py

@@ -0,0 +1,6 @@
+class Solution:    
+    def hammingWeight(self, n: int, acc: int = 0) -> int:
+        if n == 0:
+            return acc
+        
+        return self.hammingWeight(n // 2, acc + n % 2)

palindromic-substrings/dm.py

@@ -0,0 +1,23 @@
+class Solution:
+    def countPalindrome(self, s: str, left: int, right: int) -> int:
+        result = 0
+
+        while left >= 0 and right < len(s) and s[left] == s[right]:
+            result += 1
+            left -= 1
+            right += 1
+
+        return result
+
+    def countSubstrings(self, s: str) -> int:
+        total_count = 0
+
+        for i in range(len(s)):
+            left = right = i
+            total_count += self.countPalindrome(s, left, right)
+
+        for i in range(len(s) - 1):
+            left, right = i, i + 1
+            total_count += self.countPalindrome(s, left, right)
+
+        return total_count

top-k-frequent-elements/dm.py

@@ -0,0 +1,21 @@
+from typing import List
+
+
+class Solution:
+    def topKFrequent(self, nums: List[int], k: int) -> List[int]:
+        count_dict = {}
+        frequency_bucket = [[] for i in range(len(nums) + 1)]
+        result = []
+
+        for num in nums:
+            count_dict[num] = count_dict.get(num, 0) + 1
+
+        for num, count in count_dict.items():
+            frequency_bucket[count].append(num)
+
+        for i in range(len(frequency_bucket) - 1, 0, -1):
+            for num in frequency_bucket[i]:
+                result.append(num)
+
+                if len(result) == k:
+                    return result