From e1173dd1a57e5aa66930075df7c785907a02076d Mon Sep 17 00:00:00 2001
From: HC-kang <weston0713@gmail.com>
Date: Wed, 4 Dec 2024 08:47:40 +0900
Subject: [PATCH 1/5] feat: 217. Contains Duplicate

---
 contains-duplicate/HC-kang.rs | 12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 contains-duplicate/HC-kang.rs

diff --git a/contains-duplicate/HC-kang.rs b/contains-duplicate/HC-kang.rs
new file mode 100644
index 000000000..26e5191a1
--- /dev/null
+++ b/contains-duplicate/HC-kang.rs
@@ -0,0 +1,12 @@
+impl Solution {
+    pub fn contains_duplicate(nums: Vec<i32>) -> bool {
+        use std::collections::HashSet;
+        let mut set = HashSet::new();
+        for num in nums {
+            if !set.insert(num) {
+                return true;
+            }
+        }
+        false
+    }
+}

From 2a25e28ce182082722975007dfc2c4f0e704be77 Mon Sep 17 00:00:00 2001
From: HC-kang <weston0713@gmail.com>
Date: Mon, 9 Dec 2024 09:17:24 +0900
Subject: [PATCH 2/5] feat: 125. Valid Palindrome

---
 valid-palindrome/HC-kang.rs | 65 +++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 valid-palindrome/HC-kang.rs

diff --git a/valid-palindrome/HC-kang.rs b/valid-palindrome/HC-kang.rs
new file mode 100644
index 000000000..d4e6b2c11
--- /dev/null
+++ b/valid-palindrome/HC-kang.rs
@@ -0,0 +1,65 @@
+/**
+ * https://leetcode.com/problems/valid-palindrome
+ * T.C. O(n)
+ * S.C. O(n)
+ */
+impl Solution {
+    pub fn is_palindrome(s: String) -> bool {
+        let s: Vec<char> = s
+            .chars()
+            .filter(|c| c.is_alphanumeric())
+            .map(|c| c.to_ascii_lowercase())
+            .collect(); // T.C. O(n), S.C. O(n)
+            
+        let mut i = 0;
+        let mut j = s.len().saturating_sub(1);
+        
+        // T.C. O(n)
+        while i < j {
+            if s[i] != s[j] {
+                return false;
+            }
+            i += 1;
+            j -= 1;
+        }
+        true
+    }
+}
+
+/**
+ * 최적화
+ * T.C. O(n)
+ * S.C. O(1)
+ */
+impl Solution {
+    pub fn is_palindrome(s: String) -> bool {
+        let s = s.as_bytes();
+        let (mut left, mut right) = (0, s.len().saturating_sub(1));
+
+        while (left < right) {
+            while (left < right && !Self::is_alphanumeric(s[left])) {
+                left += 1;
+            }
+
+            while (left < right && !Self::is_alphanumeric(s[right])) {
+                right -= 1;
+            }
+
+            if left < right {
+                if s[left].to_ascii_lowercase() != s[right].to_ascii_lowercase() {
+                    return false;
+                }
+                left += 1;
+                right -= 1;
+            }
+        }
+
+        true
+    }
+
+    fn is_alphanumeric(c: u8) -> bool {
+        (c >= b'a' && c <= b'z') ||
+        (c >= b'A' && c <= b'Z') ||
+        (c >= b'0' && c <= b'9')
+    }
+}

From b3b9e63c933c4655a9f91a9174ea87c434763167 Mon Sep 17 00:00:00 2001
From: HC-kang <weston0713@gmail.com>
Date: Mon, 9 Dec 2024 09:18:26 +0900
Subject: [PATCH 3/5] docs: 217. Contains Duplicate

---
 contains-duplicate/HC-kang.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/contains-duplicate/HC-kang.rs b/contains-duplicate/HC-kang.rs
index 26e5191a1..9221af734 100644
--- a/contains-duplicate/HC-kang.rs
+++ b/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;

From 086c7c50517e0f9bc1cc6199c129d6086705cddd Mon Sep 17 00:00:00 2001
From: HC-kang <weston0713@gmail.com>
Date: Mon, 9 Dec 2024 20:04:26 +0900
Subject: [PATCH 4/5] docs: 125. Valid Palindrome

---
 valid-palindrome/HC-kang.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/valid-palindrome/HC-kang.rs b/valid-palindrome/HC-kang.rs
index d4e6b2c11..18a6971da 100644
--- a/valid-palindrome/HC-kang.rs
+++ b/valid-palindrome/HC-kang.rs
@@ -13,7 +13,7 @@ impl Solution {
             
         let mut i = 0;
         let mut j = s.len().saturating_sub(1);
-        
+
         // T.C. O(n)
         while i < j {
             if s[i] != s[j] {
@@ -27,7 +27,7 @@ impl Solution {
 }
 
 /**
- * 최적화
+ * 최적화 - 문자열을 복사하지 않음
  * T.C. O(n)
  * S.C. O(1)
  */

From 6a2559c38e81c8b530d4f87dcb2d72d1c6ab7ca7 Mon Sep 17 00:00:00 2001
From: HC-kang <weston0713@gmail.com>
Date: Sat, 14 Dec 2024 16:38:48 +0900
Subject: [PATCH 5/5] =?UTF-8?q?test:=20rebase=20=EC=97=86=EC=9D=B4=20?=
 =?UTF-8?q?=EC=A0=95=EC=83=81=EC=A0=81=EC=9D=B8=20=EC=A0=9C=EC=B6=9C?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 alien-dictionary/HC-kang.js | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 alien-dictionary/HC-kang.js

diff --git a/alien-dictionary/HC-kang.js b/alien-dictionary/HC-kang.js
new file mode 100644
index 000000000..ec10f3e9d
--- /dev/null
+++ b/alien-dictionary/HC-kang.js
@@ -0,0 +1 @@
+console.log('hi');