类的继承，写的有问题，求帮助
using System;using System.Collections.Generic;
using System.Text;
namespace 面积
{
public class Class1
{
private double x;
public double y;
public Class1(double m, double n)
{
x = m;
y = n;
}
public double Aera();
}
}
public class rentangle : Class1
{
public rentangle(double _x, double _y)
{
x = _x;
y = _y;
}
public override double Area()
{
return x * y;
}
}
public class circle : Class1
{
public circle(double _x)
{
x = _x;
}
public override double Area()
{
return x * x * 3.14;
}
}
错误 1 找不到类型或命名空间名称“Class1”(是否缺少 using 指令或程序集引用?) E:\c#\新建文件夹\新建文件夹\面积\面积\Class1.cs 22 30 面积
