第4题-哪个查阅窗能留空

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	luti	71ms	18.5 MiB	C++14(O2)	3 KiB	2026-8-30 20:39:50
AC	Qcef1qW8S7	106ms	20.3 MiB	C++14(O2)	3.3 KiB	2026-9-6 17:47:50
AC	t9OY6Eq6DI	177ms	13.6 MiB	C++17(O2)	2.6 KiB	2026-9-6 16:36:42
AC	47hmvGbB0I	182ms	15.4 MiB	C++14(O2)	2.9 KiB	2026-9-3 11:55:59
AC	XpV5dIQakP	290ms	15.5 MiB	C++	4.2 KiB	2026-9-12 0:32:43