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Uses graphabc, events,timers;
const
r=10 ;
d=12;
 
type
TDirection = (None, Left, Right, Up, Down);
 
var x,t,y,i,z,xr,yr,prin1,prin2,prin3,prin4,prin5,k,s4et,prin6: integer;
Direction :TDirection;
xs,ys,bufx,bufy:array[1..200]of integer;
procedure shar3;
begin
SetBrushColor(clYellow);
circle(xs[k],ys[k],r);
end;
 
procedure Circl;
begin
SetBrushColor(clBlack);
circle(x,y,r);
end;
 
procedure rshar ;
begin
xr:=Random(WindowWidth) ;
yr:=Random( WindowHeight);
end;
 
procedure rshar2;
begin
SetBrushColor(clYellow);
circle(xr,yr,r);
end;
procedure XP(Key:integer);
begin
case Key of
VK_Left: Direction := Left ;
VK_Right:Direction := Right ;
VK_UP: Direction := UP ;
VK_Down: Direction :=Down ;
end;
circle(x,y,r);
end;
 
procedure pause;
begin
for i:=1 to 1 do
begin
Circl;
rshar2;
ClearWindow;
rshar2 ;
prin1:=(xr-x+r)*(xr-x+r)+(yr-y)*(yr-y) ;
prin2:=(xr-x-r)*(xr-x-r)+(yr-y)*(yr-y) ;
prin3:=(xr-x)*(xr-x)+(yr-y+r)*(yr-y+r) ;
prin4:=(xr-x)*(xr-x)+(yr-y-r)*(yr-y-r) ;
prin5:=R*R;
if (prin1)<=(prin5) then begin
rshar ;
s4et:=s4et+1;
end;
 
if (prin2)<=(prin5) then begin
rshar ;
s4et:=s4et+1;
end;
if (prin3)<=(prin5) then begin
rshar ;
s4et:=s4et+1;
end;
if (prin4)<=(prin5) then begin
rshar ;
s4et:=s4et+1;
end;
 
case Direction of
Left: begin x:=x-d; if x<=0 then x:=WindowWidth end;
Up: begin y:=y-d; if y<=0 then y:=WindowHeight end;
Right: begin x:=x+d; if x>=WindowWidth then x:=0 end;
Down: begin y:=y+d; if y>=WindowHeight then y:=0 end;
end;
xs[1]:=x;
ys[1]:=y;
for k:=1 to s4et do
begin
bufx[k]:=xs[k];
bufy[k]:=ys[k];
 
end;
for k:=1 to s4et do
begin
xs[k+1]:=bufx[k];
ys[k+1]:=bufy[k] ;
end;
for k:=2 to s4et do
shar3;
Circl;
end;
end;
begin
 
SetWindowHeight(550);
setwindowwidth(950);
rshar;
s4et:=2;
 
Direction := None;
 
x:=WindowWidth div 2;
y:=WindowHeight div 2;
OnKeyDown:=XP;
CreateTimer(150,pause);
 
end.