There are no half-Sprints in Scrum.
The number of Sprints depends on your Sprint duration. If you had 1 week Sprints, you likely have Sprint Planning sessions on April 1, April 8, April 15, April 22, April 29, May 6, May 13, May 20, and May 27. You could also have 2 week Sprints starting on April 1, April 15, April 29, May 13, and May 27 (due to the fixed date, the final Increment would need to be delivered in less than 2 weeks). Or you could have 3 week Sprints on April 1, April 22, May 6, and May 27 (again - a final Increment would be delivered in less than 3 weeks after starting the Sprint). You could also have 4 week Sprints on April 1, April 29, May 27 (again - less than every other Sprint). Or even month long Sprints starting on April 1, May 1, and June 1.
For the Sprints that are less than the other Sprints, you have some options. You could either target a delivery earlier than the end of the effort. You would simply not do any work after the last full Sprint's review and perhaps work exclusively on transition efforts or disband early. The other option would be to plan a Sprint at less than full capacity, ending on with a Sprint Review on June 4.
And this is only considering full-week Sprints. Nothing says that a Sprint needs to be 1 week long or longer. The only rule about the length of a Sprint in Scrum is that a Sprint must be 1 month or less in duration.