【例23.2】这个月有几天

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	jerryhu	22ms	548 KiB	C++98	363 Bytes	2025-12-13 9:57:49
AC	simberwang	22ms	548 KiB	C++20(O2)	350 Bytes	2025-12-13 9:55:48
AC	frankzhao	22ms	692 KiB	C++20(O2)	306 Bytes	2025-12-13 9:56:56
AC	tobytao	22ms	540 KiB	C++20(O2)	367 Bytes	2025-12-13 9:55:59
AC	reginazhang	24ms	552 KiB	C++20(O2)	341 Bytes	2025-12-13 9:44:29
AC	raycao	24ms	544 KiB	C++20(O2)	475 Bytes	2025-9-26 18:10:21
AC	peterwei	25ms	544 KiB	C++20(O2)	472 Bytes	2025-12-18 0:58:57
AC	hankli	26ms	548 KiB	C++20	1.1 KiB	2025-9-28 13:13:47