In the recent Div. 4 contest, I only solved two problems. Back then, I set a goal to solve three problems in the next Div. 1+2 contest. Many people mocked me, thinking it was impossible for me to solve three problems, but I did it! I spent about half an hour thinking about problem A and solved it, then another half hour on problem B. Surprisingly, problem D turned out to be so straightforward! I noticed that the XOR value of $$$x$$$ and $$$x+y$$$ remains constant. Based on this insight, I wrote the code and passed D on the first try. I truly succeeded! I hope that in the next Div. 2 contest, I can solve all four problems A, B, C, and D!

Please congratulate me!

Additionally, I hope that Luogu can unblock my account.