program  dec1;
var
  n,m,i,j,ans,t:longint;
  a:array[1..200000] of longint;


procedure  sort(l,r:longint);
var
  i,j,mid:longint;
begin
  i:=l;j:=r;mid:=a[random(j-i+1)+i];
  repeat
    while a[i]<mid do inc(i);
    while a[j]>mid do dec(j);
    if not(i>j) then
      begin
        t:=a[i];
        a[i]:=a[j];
        a[j]:=t;
        inc(i);dec(j);
      end;
    until i>j;
    if l<j then sort(1,j);
    if i<r then sort(i,r);
end;



begin
  assign(input,'dec.in');
  assign(output,'dec.out');
  reset(input);
  rewrite(output);
  readln(n,m);
  for i:=1 to n do read(a[i]);
  sort(1,n);
  for i:=n downto 2 do
    for j:=i-1 downto 1 do
      if a[i]-a[j]=m then
          ans:=ans+1;
  writeln(ans);
  close(input);
  close(output);
end.