include ltiostream include ltcmath int main using namespace stdcoutltltquot请输入x的值x10quotdouble x，ycinxint nifx=10xlt20n=1else ifx=20xlt30n=2else ifx=3...

include ltstdiohint mainvoidint xint yscanfquot%dquot，x得到x的值ifxlt1y=xelse if x=1xlt12 y=5*x2else y=8*x10printfquoty= %d\nquot，yreturn 0。int main doub...