program aequip2a;
const
  Anz=2;
var
  x,y:       integer;
  Xl,Yl: array[1..Anz] of real;
  L:     array[1..Anz] of real;
  P:         real;
  DeltaP:    real;
  Eps:       real;

procedure Pot;
var
  i:  integer;
  r:     real;
  Dx,Dy: real;
begin
P:=0;
for i:=1 to Anz do
  begin
  Dx:=x-Xl[i]; Dy:=y-Yl[i];
  r:=sqrt(Dx*Dx+Dy*Dy);
  P:=P+L[i]/r;
  end;
end;

procedure Zeichne;
begin
if odd(round(P))
  then plot(x,y,1);
end;

begin
Eps:=0.1;
DeltaP:=1;
Xl[1]:=100;
Yl[1]:=100;
L[1]:=1000;
Xl[2]:=200;
Yl[2]:=-10;
L[2]:=1200;

graphmode;
for y:=0 to 63 do
  for x:=0 to 239 do
    begin
    Pot;
    Zeichne;
    end;

repeat
until keypressed;

textmode;

end.