diff --git a/csharp/Feb22/Feb22.sln b/csharp/Feb22/Feb22.sln
index 2aded55..5b977df 100644
--- a/csharp/Feb22/Feb22.sln
+++ b/csharp/Feb22/Feb22.sln
@@ -4,6 +4,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "cn-0221", "cn-0221\cn-0221.
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "int-0221", "int-0221\int-0221.csproj", "{9CCC88EF-7FA3-4406-B41B-EAC86AEF8760}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "int-0222", "int-0222\int-0222.csproj", "{70C4BB01-2740-48F5-911A-FEB254C1AAD5}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -18,5 +20,9 @@ Global
 		{9CCC88EF-7FA3-4406-B41B-EAC86AEF8760}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{9CCC88EF-7FA3-4406-B41B-EAC86AEF8760}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{9CCC88EF-7FA3-4406-B41B-EAC86AEF8760}.Release|Any CPU.Build.0 = Release|Any CPU
+		{70C4BB01-2740-48F5-911A-FEB254C1AAD5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{70C4BB01-2740-48F5-911A-FEB254C1AAD5}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{70C4BB01-2740-48F5-911A-FEB254C1AAD5}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{70C4BB01-2740-48F5-911A-FEB254C1AAD5}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal
diff --git a/csharp/Feb22/int-0222/Program.cs b/csharp/Feb22/int-0222/Program.cs
new file mode 100644
index 0000000..02f73e5
--- /dev/null
+++ b/csharp/Feb22/int-0222/Program.cs
@@ -0,0 +1,17 @@
+namespace int_0222;
+
+public class Solution {
+	public int TitleToNumber(string columnTitle) {
+		int ret = 0;
+		foreach (char c in columnTitle)
+			ret = (26 * ret) - 'A' + c + 1;
+		return ret;
+	}
+}
+
+public class Runner {
+	public static void Main() {
+		var s = new Solution();
+		Console.WriteLine(s.TitleToNumber("ZY"));
+	}
+}
\ No newline at end of file
diff --git a/csharp/Feb22/int-0222/int-0222.csproj b/csharp/Feb22/int-0222/int-0222.csproj
new file mode 100644
index 0000000..bb3d932
--- /dev/null
+++ b/csharp/Feb22/int-0222/int-0222.csproj
@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net6.0</TargetFramework>
+        <RootNamespace>int_0222</RootNamespace>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+</Project>