YellowSpace.java
package shapes;
import java.awt.Color;
import javax.swing.SwingUtilities;
import painter.SPainter;
import shapes.SCircle;
import shapes.SRectangle;
public class YellowSpace {
    public static void main(String[]args){
        double BigEdge = 400;
        double BYellowToBGray = 60;
        double SGrayToBYellow = 30;
        double SYellowToBGray = 15;
        double circle_radius = (BigEdge - BYellowToBGray*2)/2;
        SCircle C = new SCircle(circle_radius);
        SSquare BYellow = C.inscribingSquare();
        double BYellowSide = BYellow.side();
        double BYellowArea = BYellow.area();
        double circle_radius1 = (BYellowSide - SGrayToBYellow*2)/2;
        SCircle C1 = new SCircle(circle_radius1);
        SSquare SGray = C1.inscribingSquare();
        double SGrayArea = SGray.area();
        double SGraySide = SGray.side();
        double circle_radius3 = (SGraySide -(SYellowToBGray*2))/2;
        SCircle C2 = new SCircle(circle_radius3);
        SSquare SYellow = C2.inscribingSquare();
        double SYellowArea = SYellow.area();
        double YellowSpace = BYellowArea - (SGrayArea - SYellowArea);
        System.out.println(YellowSpace);




    }
}

Demo

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