为什么我两个文件都创建好了但是没法运行

Question

package ch4;
public class Example4_3f
public static void main(String[] args) t
circle c=new circle();
c.radius=5;
double perimeter=c.calPerimeter();
double area=c.calArea();
System.out. printf("%s%.1f\n"，"该圆周长：",perimeter);System.out. printf("%s%.1f\n"，"该圆面积："，area)；
]123package ch4;
4public class circle f
678 public double radius;
publicfinaldouble PI =3.14;
99 public double calPerimeter()
01  return 2*PI *radius;
20 public double calArea()t
3 return PI*radius*radius;

Answer 1

只能有一个文件里面有main，不要两个文件里都放main