program aa;
var
a,c,d,e,f,i,j,n,m,max,sum:longint;
l:array[1..200000]of longint;
f1,f2:text;
//*******************************************
procedure sort(t,r: longint);
var
  i,j,x,y: longint;
begin
  i:=t; j:=r; x:=l[(t+r) DIV 2];
  repeat
    while l[i]<x do i:=i+1;
    while x<l[j] do j:=j-1;
    if i<=j then
    begin
      y:=l[i]; l[i]:=l[j]; l[j]:=y;
      i:=i+1; j:=j-1;
    end;
  until i>j;
  if t<j then sort(t,j);
  if i<r then sort(i,r);
end;
//*******************************************
begin
assign(f1,'dec.in');
assign(f2,'dec.out');
reset(f1);
rewrite(f2);
readln(f1,n,m);
for i:=1 to n do
read(f1,l[i]);
sort(1,n);
sum:=0;
for i:=n downto 1 do
if l[i]<m then break
else
for j:=i downto 1 do
if l[i]-l[j]=m then inc(sum);
writeln(f2,sum);
close(f1);close(f2);
end.