Problem Statement not clear in ZCO12003

I am getting wrong answer in ZCO problem :

I don’t understand the alternate depth part ig
The statement is this :slight_smile:
The alternating depth of a well-bracketed sequence tells us the maximum number of times we switch between the two types of brackets when we have inner matched brackets enclosed within outer matched brackets.

Can someone pls tell me what it means
Thanks :slight_smile:

@ssjgz @everule1