Not getting the ;logic

in challenges section of segment i am not gettiing the idea to solve maximum sum query
please example this to me

For understanding thoroughly, refer this -:

I hope I’ve cleared your doubt. I ask you to please rate your experience here
Your feedback is very important. It helps us improve our platform and hence provide you
the learning experience you deserve.

On the off chance, you still have some questions or not find the answers satisfactory, you may reopen
the doubt.