Area and circumference of circle

import java.util.*;
class Circle
{
    public static void main(String args[])
    {
        float r,area,cir;
        System.out.println("For Circle:");
        System.out.println("Enter radius:");
        cir=2*3.14*r;
        area=3.14*r*r;
        System.out.println("The area of circle="+area);
        System.out.println("The circumference of circle:"+cir);
    }
}