public void C7(int bok, int depth ){
        if (depth < 0) {
           return;
        }
        C7(bok/3, depth-1);
        for(int j=0;j<4;j++){
            forward(2*bok/3);
            C7(bok/3, depth-1);
            back(2*bok/3);
            right(90);
        }
    }


alg.C7(450, 5);