var
  n,r,max,ans,i,j:longint;
  x,y:array[0..100000]of longint;

function dis(i,j:longint):double;
begin
  dis:=sqrt(sqr(x[i]-x[j])+sqr(y[i]-y[j]));
end;

begin
  assign(input,'fight.in'); reset(input);
  assign(output,'fight.out'); rewrite(output);
  readln(n,r);
  for i:=1 to n do read(x[i],y[i]);
  max:=-maxlongint;
  for i:=1 to n do
  begin
    ans:=0;
    for j:=1 to n do
    if dis(i,j)<=r then inc(ans);
    if ans>max then max:=ans;
  end;
  writeln(max);
  close(input);
  close(output);
end.