MrPython @ 2024-08-14 19:37:00
考虑有个nan这种奇葩东西。
根据cppreference,比较的类型需满足具名要求“比较”(https://zh.cppreference.com/w/cpp/named_req/Compare)。
(std::less<double>())(nan,a) 在a是任何数字时都为false,即equiv(a, nan),而他不具有传递性
这样,double不满足比较具名要求,从语言层面讲是ub
实际操作时,在排序含有nan的数据时会ub。
by Crystal_camellia @ 2024-08-14 19:37:14
qp
by All_Failed_OI_Cici @ 2024-08-14 19:37:27
qp
by Crystal_Rose @ 2024-08-14 19:37:45
qp
by rui_er @ 2024-08-14 19:37:49
难绷
by da_ke @ 2024-08-14 19:38:23
@MrPython not a number(难nan) 总是会莫名出现qwq,这下好了。
by Y_zhao111 @ 2024-08-14 19:38:25
qp
by EverNight37 @ 2024-08-14 19:38:43
qp
by bryce @ 2024-08-14 19:39:02
qp
by qiuzijin2026 @ 2024-08-14 19:39:06
qp
by ceh666 @ 2024-08-14 19:39:18
@MrPython qp