diff --git a/mustergenerator.py b/mustergenerator.py
index a905875..2631b80 100644
--- a/mustergenerator.py
+++ b/mustergenerator.py
@@ -5,7 +5,6 @@ import math
 
 class Circle:
     def __init__(self, name: str, filepath: str, length=1000, height=1000, radius=10, distance=60, offset=50):
-        # run validations
         assert length >= 0, "length can not be negative"
         assert height >= 0, "height can not be negative"
         assert radius >= 0, "radius can not be negative"
@@ -13,7 +12,6 @@ class Circle:
         assert offset >= 0, "offset can only be 0 - 100 %"
         assert offset <= 100, "offset can only be 0 - 100 %"
 
-        # Assign to self object
         self.__length = length
         self.__height = height
         self.__radius = radius
@@ -108,26 +106,31 @@ if __name__ == '__main__':
         print(f"\nStandardwerte\nHöhe: {circle.height} px\nLänge: {circle.length} px\nRadius: {circle.radius} px\nAbstand: {circle.distance} px\nOffset: {circle.offset_percentage} %\n")
         selection_flag = True
         while selection_flag:
-            parameter_selection = int(input("Parameter ändern (0: keinen Parameter ändern, 1: Höhe, 2: Länge, 3: Radius, 4: Abstand, 5: Offste):"))
-            if parameter_selection == 0:
-                selection_flag = False
-            elif parameter_selection == 1:
-                height = int(input("Höhe in Pixeln eingeben:"))
-                circle.height = height
-            elif parameter_selection == 2:
-                length = int(input("Länge in Pixeln:"))
-                circle.length = length
-            elif parameter_selection == 3:
-                radius = int(input("Radius in Pixeln:"))
-                circle.radius = radius
-            elif parameter_selection == 4:
-                distance = int(input("Abstand in Pixeln:"))
-                circle.distance = distance
-            elif parameter_selection == 5:
-                offset = int(input("Offset in %:"))
-                circle.offset = offset
-            else:
+            try:
+                parameter_selection = int(input("Parameter ändern (0: keinen Parameter ändern, 1: Höhe, 2: Länge, 3: Radius, 4: Abstand, 5: Offste):"))
+                if parameter_selection == 0:
+                    selection_flag = False
+                elif parameter_selection == 1:
+                    height = int(input("Höhe in Pixeln eingeben:"))
+                    circle.height = height
+                elif parameter_selection == 2:
+                    length = int(input("Länge in Pixeln:"))
+                    circle.length = length
+                elif parameter_selection == 3:
+                    radius = int(input("Radius in Pixeln:"))
+                    circle.radius = radius
+                elif parameter_selection == 4:
+                    distance = int(input("Abstand in Pixeln:"))
+                    circle.distance = distance
+                elif parameter_selection == 5:
+                    offset = int(input("Offset in %:"))
+                    circle.offset = offset
+                else:
+                    print("ungültiger Wert")
+            except ValueError:
                 print("ungültiger Wert")
+            except AssertionError as error:
+                print(error)
 
         circle.circle_generation()
     elif shape == 2: