circle.java

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public class Circle{
 private double radius;
  
  public Circle(double r){
  	  this.radius = r;
  }
  public void setRadius(double r){
    radius = r;
}
 public double getRadius(){
    return radius;
}
  public double perimeter(){
    return 2*Math.PI*radius;
  }
  public double area(){
    return Math.PI*radius*radius;
  }
}