From d740e709ae0a0649dd5db91a035e0c13d85db1ac Mon Sep 17 00:00:00 2001
From: Sangmin <sm9171@nate.com>
Date: Wed, 16 Apr 2025 00:39:54 +0900
Subject: [PATCH 1/2] feat: valid-palindrome solution

---
 valid-palindrome/sm9171.java | 12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 valid-palindrome/sm9171.java

diff --git a/valid-palindrome/sm9171.java b/valid-palindrome/sm9171.java
new file mode 100644
index 000000000..02327de15
--- /dev/null
+++ b/valid-palindrome/sm9171.java
@@ -0,0 +1,12 @@
+class Solution {
+    public boolean isPalindrome(String s) {
+        String str = s.toLowerCase().replaceAll("[^a-z0-9]","");
+        char[] charArray = str.toCharArray();
+        for (int i = 0; i < charArray.length / 2; i++) {
+            if (charArray[i] != charArray[charArray.length - i - 1]) {
+                return false;
+            }
+        }
+        return true;
+    }
+}

From 68407bf1ccc1f98957df6f091da69ccfdae2f284 Mon Sep 17 00:00:00 2001
From: Sangmin <sm9171@nate.com>
Date: Sun, 20 Apr 2025 16:17:43 +0900
Subject: [PATCH 2/2] feat: number-of-1-bits solution

---
 number-of-1-bits/sm9171.java | 8 ++++++++
 1 file changed, 8 insertions(+)
 create mode 100644 number-of-1-bits/sm9171.java

diff --git a/number-of-1-bits/sm9171.java b/number-of-1-bits/sm9171.java
new file mode 100644
index 000000000..652e70150
--- /dev/null
+++ b/number-of-1-bits/sm9171.java
@@ -0,0 +1,8 @@
+public static int hammingWeight(int n) {
+    int sum = 0;
+    while (n > 0) {
+        sum += n % 2;
+        n /= 2;
+    }
+    return sum;
+}