9. Palindrome Number

9. Palindrome Number/9. Palindrome Number.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net8.0</TargetFramework>
+        <RootNamespace>_9._Palindrome_Number</RootNamespace>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+</Project>

9. Palindrome Number/Program.cs

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+// See https://aka.ms/new-console-template for more information
+
+using _9._Palindrome_Number;
+
+var sol = new Solution();
+Console.WriteLine(sol.IsPalindrome(0));

9. Palindrome Number/Solution.cs

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+namespace _9._Palindrome_Number;
+
+public class Solution
+{
+    public bool IsPalindrome(int x)
+    {
+        if (x < 0)
+            return false;
+        if (x < 10)
+            return true;
+        List<byte> digits = new List<byte>(32);
+        while (x != 0)
+        {
+            digits.Add((byte)(x%10));
+            x /= 10;
+        }
+
+        int half = digits.Count / 2;
+        for (int i = 0; i < half; i++)
+            if (digits[i] != digits[digits.Count - 1 - i])
+                return false;
+
+        return true;
+    }
+}