输出保留 3 位小数的浮点数

Status	Submit By	Time	Memory	Language	Code	Submit At
AC	BC20260085	31ms	844 KiB	C++11	117 Bytes	2023-11-24 17:06:16
AC	BC20260023	31ms	688 KiB	C++11	107 Bytes	2023-12-5 15:17:02
AC	BC20260028	31ms	848 KiB	C++11	168 Bytes	2023-11-24 16:29:34
AC	CC20260060	31ms	808 KiB	C++11	118 Bytes	2023-11-12 7:41:31
AC	BC20260311	32ms	700 KiB	C++17	202 Bytes	2023-12-12 15:53:33
AC	BC20260349	32ms	760 KiB	C++17(O2)	117 Bytes	2023-10-20 22:21:55
AC	CC20260191	38ms	796 KiB	C++17(O2)	131 Bytes	2023-10-6 11:52:50
AC	BC20260080	39ms	692 KiB	C++17(O2)	180 Bytes	2024-4-3 23:44:14
AC	C20250070	41ms	808 KiB	C++17(O2)	135 Bytes	2024-5-18 11:19:30
AC	BC20260087	42ms	784 KiB	C++17(O2)	118 Bytes	2024-4-8 15:19:17
AC	BC20260030	44ms	888 KiB	C++17(O2)	180 Bytes	2024-4-11 19:52:50
AC	BC20260002	44ms	808 KiB	C++17	202 Bytes	2024-5-13 12:13:53