docs: 217. Contains Duplicate

Author: HC-kang

contains-duplicate/HC-kang.rs

@@ -1,3 +1,8 @@
+/**
+ * https://leetcode.com/problems/contains-duplicate
+ * T.C. O(n)
+ * S.C. O(n)
+ */
 impl Solution {
     pub fn contains_duplicate(nums: Vec<i32>) -> bool {
         use std::collections::HashSet;