什么是四则混合运算是的哪四则

简介：Blue smoke filled the air, and Li Dao walked out with a pale face. This technique was extremely powerful, but the load on him was also extremely heavy, so it hurt his vitality. However, his face was gloomy at the moment, because he found that the old man did not He was killed by this technique, but when the thunder came, he instantly turned into a bloody light and disappeared.