diff --git a/u04/Rotation.class b/u04/Rotation.class
new file mode 100644
index 0000000..7f84ca3
Binary files /dev/null and b/u04/Rotation.class differ
diff --git a/u04/Rotation.java b/u04/Rotation.java
new file mode 100644
index 0000000..84daaa0
--- /dev/null
+++ b/u04/Rotation.java
@@ -0,0 +1,22 @@
+public class Rotation {
+    public static void main(String[] args) {
+        int x= 2;
+        int y= 3;
+
+        // --------------------------------------
+        // | Hier fehlt Ihr Code
+        // | Verwenden Sie einfache Zuweisungen
+
+
+        int tmp = x;
+        x = y;
+        y = -tmp;
+
+
+
+        // | Ende Ihres Codes
+        // --------------------------------------
+
+        System.out.println(x + " " + y);
+    }
+}