C. White Sheet There is a white sheet of paper lying on a rectangle table. The sheet is a rectangle with its sides parallel to the sides of the table. If you will take a look from above and assume that the bottom left corner of the table has coordina
//两值交换 public static void Show(ref int num1,ref int num2) { int num=num1; num1=num2; num2=num; } static void Mian(string [] args) { int num1=7; int num2=4; console.WritLine("交换前,num1:{0},num2:{1}",num1,num2); Show(ref num1,ref num2); console.Wri