function ball()
x=[64,64,64];
y=[64,64,64];
a=[3,4,5];
b=[9,8,7];
r=10;
for i=1:200
    B=ones(128)*256;
    for p=1:3
    for j=1:128
        for k=1:128
            if sqrt((x(p)-j)^2+(y(p)-k)^2)<r
                B(j,k)=0;
            end
        end
    end
        if (x(p)<=r)
        a(p)=abs(a(p));
    elseif (x(p)>=128-r)
        a(p)=abs(a(p))*(-1);
    elseif (y(p)<=r)
        b(p)=abs(b(p));
    elseif (y(p)>=128-r)
        b(p)=abs(b(p))*(-1);
    end
    end
    imshow(B);
    %%pause;close;
    x=x+a;
    y=y+b;
c=a;
d=b;
%for p=1:3 %%peng
%for q=p:3
 % if sqrt((x(p)-x(q))^2+(y(p)-y(q))^2)<=r  
%X=solve('xah+xbh=a(p)+a(q)','yah+ybh=b(p)+b(q)','xah^2+xbh^2+yah^2+ybh^2=a(p)^2+a(q)^2+b(p)^2+b(q)^2','(xah-a(p))*(y(p)-y(q))=(x(p)-x(q))*(yah-b(p))','(xah-ap)*(yp-yq)=(xp-xq)*(yah-bp)','xah,yah,xbh,ybh');
%c(p)=X.xah;    
%d(p)=X.yah;
%c(q)=X.xbh;
%d(q)=X.ybh;
 % end  
%end
end
a=c;
b=d;
end