简便算法如下:36+36×1983+360×1985=36x1+36×1983+36×19850=36x(1+1983+19850)=36x21834=786024
36+36×1983+360×1985=36+36×1983+36×1985×10=36×(1+1983+19850)=36×21834=786024
36+36(1983+1985)