【例70.2】求A-B字符串

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	李衍树xly2025	28ms	504 KiB	C++14(O2)	612 Bytes	2025-7-25 14:18:11
AC	王思懿	29ms	544 KiB	C++17(O2)	367 Bytes	2025-12-23 22:13:24
AC	chenqiugu	34ms	760 KiB	C++14	426 Bytes	2025-8-6 22:30:39
AC	taoruiguo120	37ms	512 KiB	C++14	311 Bytes	2025-8-1 18:34:05