program river;
const maxm=100;
var x,p:array [0..maxm] of longint;
    b:array [-10..90] of boolean;
    c:array [0..maxm,0..9] of longint;
    L,s,t,m,n,i,j,v,k,best,min:longint;
  function can(len:longint):boolean;
  begin
    if len<0
    then can:=false
    else if len>=s*s-s
         then can:=true
         else can:=b[len]
  end;
begin
  assign(input,'river.in');
  reset(input);
  readln(L);
  readln(s,t,m);
  for i:=1 to m do read(x[i]);
  n:=0;
  for i:=1 to m do
    if x[i]<L
    then begin
           inc(n);
           p[n]:=x[i]
         end;
  readln;
  close(input);
  if s=t
  then begin
         best:=0;
         for i:=1 to m do
           if p[i] mod s=0
           then inc(best);
         assign(output,'river.out');
         rewrite(output);
         writeln(best);
         close(output);
         halt
       end;
  fillchar(b,sizeof(b),false);
  b[0]:=true;{-10..90}
  for i:=1 to s*s-s-1 do
    for j:=s to t do
      b[i]:=b[i] or b[i-j];
  for i:=1 to n-1 do
    for j:=1 to n-1 do
      if p[j]>p[j+1]
      then begin
             v:=p[j];
             p[j]:=p[j+1];
             p[j+1]:=v
           end;
  p[0]:=0;
  for i:=0 to n do
    for j:=0 to t-1 do
      c[i,j]:=n+1;
  c[0,0]:=0;
  for i:=1 to n do
    for j:=0 to t-1 do
      if p[i]-j<=p[i-1]
      then c[i,j]:=c[i-1,j-p[i]+p[i-1]]
      else begin
             min:=n+1;
             for k:=0 to t-1 do
               if can(p[i]-j-p[i-1]+k) and (c[i-1,k]<min)
               then min:=c[i-1,k];
             if j=0 then c[i,j]:=min+1 else c[i,j]:=min
           end;
  best:=n+1;
  for i:=0 to t-1 do
    if c[n,i]<best
    then best:=c[n,i];
  assign(output,'river.out');
  rewrite(output);
  writeln(best);
  close(output)
end.