【例7.1】保留3位小数

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	王浩泽 (zdqz202577)	7ms	504 KiB	C++14(O2)	117 Bytes	2025-12-14 21:23:14
AC	蓝牙 (lqst2554)	7ms	504 KiB	C++14(O2)	169 Bytes	2025-12-18 17:49:39
AC	周政仰 (lqst2025051)	8ms	764 KiB	C++14(O2)	115 Bytes	2025-4-15 19:40:19
AC	lfyst2422	8ms	508 KiB	C++14(O2)	130 Bytes	2025-4-16 18:15:07
AC	lfy48	9ms	536 KiB	C++14(O2)	118 Bytes	2025-3-21 17:59:55
AC	邵名慧 (lfyst2025021)	9ms	504 KiB	C++14(O2)	125 Bytes	2025-4-11 17:56:22
AC	王钰凯 (lfyst2025022)	9ms	508 KiB	C++14(O2)	116 Bytes	2025-4-9 18:21:12
AC	lfyst2414	9ms	536 KiB	C++14(O2)	124 Bytes	2025-3-22 14:23:08