using System; namespace ConsoleApplication { class stu { private string name; private int age; public stu() { name = ""; age = -1; } public stu(string n, int a) { name = n; age = a; } public void Print() { Console.Write(name + ":" + age); } } class Program { static void Main(string[] args) { stu a=new stu("xiaoming",10); a.Print(); Console.WriteLine(); stu b = new stu(); b.Print(); Console.Read(); } } }