将字符串中的小写字母转换成大写字母

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	chengweisun	21ms	512 KiB	C++20(O2)	241 Bytes	2025-12-6 11:23:28
AC	samuelgao	21ms	500 KiB	C++20	259 Bytes	2025-12-6 11:23:46
AC	xianyinli	22ms	548 KiB	C++20(O2)	186 Bytes	2025-12-6 11:19:07
AC	carlosdeng	22ms	552 KiB	C++20(O2)	220 Bytes	2025-12-6 11:24:08
AC	ericyu	22ms	524 KiB	C++20	222 Bytes	2025-12-6 11:24:59
AC	leomo	22ms	580 KiB	C++20(O2)	212 Bytes	2025-12-6 11:22:42
AC	williamyu	24ms	512 KiB	C++98	270 Bytes	2025-12-6 11:21:33