fix infinity loop

app.py

@@ -54,9 +54,8 @@ def main():
 	]
 	example = examples[random.randint(0, len(examples)-1)]
 	previous_example = example
-	while change_example or example==previous_example:
+	while change_example and example==previous_example:
 		example = examples[random.randint(0, len(examples)-1)]
-	change_example=False
 	previous_example = example
 	input_complex_sentence = st.text_area("Please type a Complex Sentence to split",example)