added things

Algorithms/Exercices1.cs

@@ -0,0 +1,37 @@
+namespace Algorithms;
+using System;
+using Algorithms.NumberTheory;
+
+class SolutionExercices1 {
+
+    public static string removeTitle(string header)
+    {
+        int idx = header.IndexOf(".");
+        return header.Substring(idx + 1);
+    }
+
+    public static void printEachDirectoryOnPath(string path)
+    {
+        string[] subs = path.Split(':');
+
+        foreach (var sub in subs)
+        {
+            Console.WriteLine(sub);
+        }
+    }
+
+    public static void Main_(String[] args){
+        // {titre}.{sous-titre}.{sous-sous- titre}
+        // 4.56.2 -> 56.2
+        // 4.b.ii  -> b.ii
+        string header = "4.56.2";
+        Console.WriteLine(removeTitle("4.56.2")); // "56.2"
+        Console.WriteLine(removeTitle("4.b.ii")); // "b.ii"
+        Console.WriteLine(removeTitle("")); // ""
+        Console.WriteLine(removeTitle("4.b")); // "b"
+
+
+        string? path = Environment.GetEnvironmentVariable("PATH");
+        printEachDirectoryOnPath(path ?? "");
+    }
+}