week 3 solutions

Author: i-mprovising

number-of-1-bits/i-mprovising.py

@@ -0,0 +1,9 @@
+"""
+Time complexity O(n)
+Space complexity O(1)
+"""
+
+class Solution:
+    def hammingWeight(self, n: int) -> int:
+        return bin(n).count('1')
+        

valid-palindrome/i-mprovising.py

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+"""
+Time complexity O(n)
+Space complexity O(n)
+"""
+
+class Solution:
+    def isPalindrome(self, s: str) -> bool:
+        # preprocessing
+        string = [c for c in s.lower() if c.isalnum()]
+
+        if string == [c for c in string[::-1]]:
+            return True
+        return False