diff --git a/.gitea/workflows/test.yml b/.gitea/workflows/test.yml
index a15ca23..eb2706c 100644
--- a/.gitea/workflows/test.yml
+++ b/.gitea/workflows/test.yml
@@ -17,6 +17,4 @@ jobs:
       - name: "🏗️ Build"
         run: dotnet build
       - name: "✅ Test"
-        run: dotnet test
-      - name: "Sophie bah caca"
-        run: echo "Louis est le meilleur"
\ No newline at end of file
+        run: dotnet test
\ No newline at end of file
diff --git a/B2BEpita.sln b/B2BEpita.sln
index 3a313a8..a87d67e 100644
--- a/B2BEpita.sln
+++ b/B2BEpita.sln
@@ -4,6 +4,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Iteration", "Iteration\Iter
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Tests", "Tests\Tests.csproj", "{A838FD78-1D97-4191-91BF-FF439C9FB918}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Stream", "Stream\Stream.csproj", "{43060AB1-3A2B-4EEE-AC6E-A476EDDC71A2}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -18,5 +20,9 @@ Global
 		{A838FD78-1D97-4191-91BF-FF439C9FB918}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{A838FD78-1D97-4191-91BF-FF439C9FB918}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{A838FD78-1D97-4191-91BF-FF439C9FB918}.Release|Any CPU.Build.0 = Release|Any CPU
+		{43060AB1-3A2B-4EEE-AC6E-A476EDDC71A2}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{43060AB1-3A2B-4EEE-AC6E-A476EDDC71A2}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{43060AB1-3A2B-4EEE-AC6E-A476EDDC71A2}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{43060AB1-3A2B-4EEE-AC6E-A476EDDC71A2}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal
diff --git a/B2BEpita.sln.DotSettings.user b/B2BEpita.sln.DotSettings.user
index 13bc7bc..fa6cf13 100644
--- a/B2BEpita.sln.DotSettings.user
+++ b/B2BEpita.sln.DotSettings.user
@@ -1,4 +1,4 @@
 <wpf:ResourceDictionary xml:space="preserve" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:s="clr-namespace:System;assembly=mscorlib" xmlns:ss="urn:shemas-jetbrains-com:settings-storage-xaml" xmlns:wpf="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
-	<s:String x:Key="/Default/Environment/UnitTesting/UnitTestSessionStore/Sessions/=394010b2_002Df74a_002D42b6_002D8445_002D2a75606c26a3/@EntryIndexedValue">&lt;SessionState ContinuousTestingMode="0" IsActive="True" Name="All tests from &amp;lt;Tests&amp;gt;" xmlns="urn:schemas-jetbrains-com:jetbrains-ut-session"&gt;
+	<s:String x:Key="/Default/Environment/UnitTesting/UnitTestSessionStore/Sessions/=6f052d53_002D9b1d_002D49af_002D8be5_002Da3b6ca9fbd46/@EntryIndexedValue">&lt;SessionState ContinuousTestingMode="0" IsActive="True" Name="All tests from &amp;lt;Tests&amp;gt;" xmlns="urn:schemas-jetbrains-com:jetbrains-ut-session"&gt;
   &lt;Project Location="/Users/louisgallet/Developer/EPITA/B2BEpita/Tests" Presentation="&amp;lt;Tests&amp;gt;" /&gt;
 &lt;/SessionState&gt;</s:String></wpf:ResourceDictionary>
\ No newline at end of file
diff --git a/Iteration/Recursion.cs b/Iteration/Recursion.cs
new file mode 100644
index 0000000..31ebab1
--- /dev/null
+++ b/Iteration/Recursion.cs
@@ -0,0 +1,35 @@
+namespace Iteration;
+
+public class Recursion
+{
+    public static bool IsAlphanum(string s, int i)
+    {
+        if (i >= s.Length)
+        {
+            return true;
+        }
+        else
+        {
+            if ((s[i] >= 'a' && s[i] <= 'z') || (s[i] >= 'A' && s[i] <= 'Z') || (s[i] >= '0' && s[i] <= '9'))
+            {
+                return IsAlphanum(s, i + 1);
+            }
+            else
+            {
+                return false;
+            }
+        }
+    }
+
+    public static string ReverseStr(string source, int lenght)
+    {
+        if (lenght == 0)
+        {
+            return "";
+        }
+        else
+        {
+            return source[lenght - 1] + ReverseStr(source, lenght - 1);
+        }
+    }
+}
\ No newline at end of file
diff --git a/Stream/Program.cs b/Stream/Program.cs
new file mode 100644
index 0000000..e5dff12
--- /dev/null
+++ b/Stream/Program.cs
@@ -0,0 +1,3 @@
+// See https://aka.ms/new-console-template for more information
+
+Console.WriteLine("Hello, World!");
\ No newline at end of file
diff --git a/Stream/Stream.cs b/Stream/Stream.cs
new file mode 100644
index 0000000..603bc08
--- /dev/null
+++ b/Stream/Stream.cs
@@ -0,0 +1,10 @@
+namespace Stream;
+using System.IO;
+
+public class Stream
+{
+    public static bool ExistFile(string path)
+    {
+        return File.Exists(path);
+    }
+}
\ No newline at end of file
diff --git a/Stream/Stream.csproj b/Stream/Stream.csproj
new file mode 100644
index 0000000..2b14c81
--- /dev/null
+++ b/Stream/Stream.csproj
@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net7.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+</Project>
diff --git a/Tests/Interatif/RecursionTest.cs b/Tests/Interatif/RecursionTest.cs
new file mode 100644
index 0000000..72f617d
--- /dev/null
+++ b/Tests/Interatif/RecursionTest.cs
@@ -0,0 +1,27 @@
+namespace Tests.Recursion;
+
+public class RecursionTest
+{
+    [Theory]
+    [InlineData("abcdef132", 0, true)]
+    [InlineData("!abcdef", 0, false)]
+    [InlineData("!abcdef", 1, true)]
+    [InlineData("abcdef!", 15, true)]
+    
+    public void IsAlphanumTest(string s, int i, bool expected)
+    {
+        bool actual = Iteration.Recursion.IsAlphanum(s, i);
+        Assert.Equal(expected, actual);
+    }
+    
+    [Theory]
+    [InlineData("42", 2, "24")]
+    [InlineData("123", 3, "321")]
+    [InlineData("ABcdeF",6, "FedcBA")]
+    
+    public void ReverseStrTest(string source, int lenght, string expected)
+    {
+        string actual = Iteration.Recursion.ReverseStr(source, lenght);
+        Assert.Equal(expected, actual);
+    }
+}
\ No newline at end of file
diff --git a/Tests/Stream/StreamTest.cs b/Tests/Stream/StreamTest.cs
new file mode 100644
index 0000000..0139eea
--- /dev/null
+++ b/Tests/Stream/StreamTest.cs
@@ -0,0 +1,6 @@
+namespace Tests.Stream;
+
+public class StreamTest
+{
+    
+}
\ No newline at end of file