namespace Lesson8_封装_静态类和静态构造函数练习
{
    static class Calc
    {
        private static float PI = 3.1415926f;
        public static float CalcCirclePerimeter(int r)
        {
            return PI * r * 2;
        }
        public static float CalcCircleArea(int r)
        {
            return PI * r * r;
        }
        public static int CalcRectanglePerimeter(int h,int w)
        {
            return (h + w) * 2;
        }
        public static int CalcRectangleArea(int h, int w)
        {
            return h * w;
        }
        public static int Absolute(int num)
        {
            if (num < 0)
            {
                return -num;
            }
            else
            {
                return num;
            }
        }

    }
    internal class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello, World!");
            Console.WriteLine(Calc.CalcRectanglePerimeter(5,10));
            Console.WriteLine(Calc.CalcRectangleArea(5, 10));
            Console.WriteLine(Calc.CalcCirclePerimeter(3));
            Console.WriteLine(Calc.CalcCircleArea(3));
            Console.WriteLine(Calc.Absolute(123));
            Console.WriteLine(Calc.Absolute(-321));
        }
    }
}