Added Fakultaet.java as a Example for friday

src/Fakultaet.java

@@ -0,0 +1,20 @@
+class Fakultaet {
+    public int fak(int number) {
+        if (number < 0) {
+            return 1;
+        }
+        int factorial = 1;
+        int i = 1;
+        while(i <= number){
+            factorial = factorial * i;
+            i = i + 1;
+        }
+
+        return factorial;
+    }
+    public static void main(String[] args) {
+        Fakultaet f = new Fakultaet();
+        int result = f.fak(5);
+        print(result);
+    }
+}