namespace _015_练习5和6 {
class Program {
static void Main(string[] args) {
//Console.WriteLine("请输入上底");
//string str1 = Console.ReadLine();
//double num1 = Convert.ToDouble(str1);
//Console.WriteLine("请输入下底");
//string str2 = Console.ReadLine();
//double num2 = Convert.ToDouble(str2);
//Console.WriteLine("请输入梯形的高");
//string str3 = Console.ReadLine();
//double num3 = Convert.ToDouble(str3);
//Console.WriteLine("梯形的面积是：");
//double res = ((num1 + num2)*num3)/2;
//Console.WriteLine(res);
Console.WriteLine("请输入圆的半径");
string str = Console.ReadLine();
double n = Convert.ToDouble(str);
Console.WriteLine("圆的周长是:" + (2 * n * 3.14));
Console.WriteLine("圆的面积是:" + (n * n * 3.14));
Console.ReadKey();
}
}
}
