diff --git a/classes/hund.cpp b/classes/hund.cpp
new file mode 100644
index 0000000..bc99488
--- /dev/null
+++ b/classes/hund.cpp
@@ -0,0 +1,12 @@
+// #include "tier.cpp"
+
+class hund : public tier
+{
+    public:
+        hund();
+};
+
+hund::hund() : tier()
+{
+    Laut =  "wuff";
+}
\ No newline at end of file
diff --git a/classes/katze.cpp b/classes/katze.cpp
new file mode 100644
index 0000000..4959af9
--- /dev/null
+++ b/classes/katze.cpp
@@ -0,0 +1,12 @@
+// #include "tier.cpp"
+
+class katze : public tier
+{
+    public:
+        katze();
+};
+
+katze::katze() : tier()
+{
+    Laut =  "miau";
+}
\ No newline at end of file
diff --git a/classes/main.cpp b/classes/main.cpp
new file mode 100644
index 0000000..4adc7ec
--- /dev/null
+++ b/classes/main.cpp
@@ -0,0 +1,13 @@
+#include "tier.cpp"
+#include "hund.cpp"
+#include "katze.cpp"
+#include <stdio.h>
+#include <iostream>
+#include <string>
+
+int main(){
+    katze a;
+    std::string laut = a.getLaut();
+    std::cout << laut << std::endl; 
+    return 0;
+}
\ No newline at end of file
diff --git a/classes/makefile b/classes/makefile
new file mode 100644
index 0000000..9e58628
--- /dev/null
+++ b/classes/makefile
@@ -0,0 +1,5 @@
+dev: compile run
+compile:
+	g++ -o program main.cpp
+run: 
+	./program	
\ No newline at end of file
diff --git a/classes/program b/classes/program
new file mode 100755
index 0000000..fbb60f2
Binary files /dev/null and b/classes/program differ
diff --git a/classes/tier.cpp b/classes/tier.cpp
new file mode 100644
index 0000000..66b0190
--- /dev/null
+++ b/classes/tier.cpp
@@ -0,0 +1,22 @@
+#include<stdio.h>
+#include <string>
+
+class tier{
+    public:
+        tier();
+
+        std::string getLaut();
+    protected:
+        std::string Laut;
+};
+
+tier::tier() {
+this->Laut = "void";
+
+}    
+
+std::string tier::getLaut()
+{
+
+    return this->Laut;
+}
\ No newline at end of file
diff --git a/fibonacci/#main.cpp# b/fibonacci/#main.cpp#
new file mode 100644
index 0000000..b55525c
--- /dev/null
+++ b/fibonacci/#main.cpp#
@@ -0,0 +1,6 @@
+#include<iostream>
+
+int fib(int n)
+{
+    return n < 2 ? 1 : fib(n-2)+ fib(n-1);
+}