int r = 5; double pi=3.14;
double p = 2 * pi * r;
double s = pi * r * r;
Console.WriteLine("周长:{0},面积:{1}", p, s);
Console.ReadKey();
int r = 5; double pi=3.14;
double p = 2 * pi * r;
double s = pi * r * r;
Console.WriteLine("周长:{0},面积:{1}", p, s);
Console.ReadKey();