How can I put a message in a jsf page after an action in another page?

Hi everybody, I know that what I try to explain is a bit difficult to
understand without know all the context but I try to do it the same:).
I have a datatable that contains a list of student. In another page I
insert a new student. When I click on "save" button I save the new
student and I return to the page with the datatable. The problem is:
when I add a student I must notify the user that the student is added
correctly with a message in the 1st page like "The student is added
correctly". This message must display only after I added the student
not when I see for the first time the page with the datatable. How can
i do this? Thanks to all.

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