[hi-rachel] WEEK 01 solutions

contains-duplicate/hi-rachel.py

@@ -0,0 +1,28 @@
+"""
+https://leetcode.com/problems/contains-duplicate/
+
+Given an integer array nums,
+return true if any value appears at least twice in the array,
+and return false if every element is distinct.
+
+TC: O(n)
+SC: O(n)
+"""
+
+from typing import List
+
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        seen = set()
+
+        for num in nums:
+            if num in seen:
+                return True
+            else:
+                seen.add(num)
+        return False
+
+
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        return len(set(nums)) != len(nums)