【例21.3】字符类型判断

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	周弈文	11ms	504 KiB	C++14	315 Bytes	2025-12-21 12:02:50
AC	马梓睿	12ms	532 KiB	C++14	264 Bytes	2025-12-21 12:01:09
AC	王宇泽	14ms	504 KiB	C++14	268 Bytes	2025-12-21 11:59:42
AC	小赵老师	14ms	532 KiB	C++14	313 Bytes	2025-12-21 11:55:58