【C++】isnan isinf
https://blog.csdn.net/ccf19881030/article/details/102596938
https://blog.csdn.net/sunyoop/article/details/79295480?spm=1001.2101.3001.6650.4&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-4-79295480-blog-102596938.t0_layer_eslanding_sa&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-4-79295480-blog-102596938.t0_layer_eslanding_sa&utm_relevant_index=9
https://blog.csdn.net/qq_39534332/article/details/91042320?spm=1001.2101.3001.6650.9&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-9-91042320-blog-102596938.t0_layer_eslanding_sa&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-9-91042320-blog-102596938.t0_layer_eslanding_sa&utm_relevant_index=14
https://vimsky.com/examples/usage/isnormal-in-c.html
https://blog.csdn.net/cumubi7552/article/details/107795527