#include<bits/stdc++.h>
using namespace std;
int main()
{
double pi;
cout<<" 有关圆的计算器"<<endl<<endl<<" power by yaotiancheng"<<endl<<endl;
cout<<"请输入圆周率取值:";
cin>>pi;
double r;
cout<<"请输入半径";
cin>>r;
double c=(2*r)*pi;
double s=(r*r)*pi;
cout<<"c="<<c<<endl<<"s="<<s<<endl<<endl;
for(long long i=0; i<1000000000; ++i)
{
}
cout<<"谢谢使用!qq:2594418727"<<endl<<"请关闭此窗口......";
while(1)
{
}
return 0;
}