{分班 NOIP模拟2010-11-18
 水题
 Author: yangbohua
 Time: 2010-11-18}

program groupa;
var
  a:array[0..5000] of longint;
  n,i,sum,l,r,max1,max2:longint;

begin
  assign(input,'groupa.in');
  reset(input);
  assign(output,'groupa.out');
  rewrite(output);
  readln(n);
  sum:=0;
  for i:=1 to n do
  begin
    read(a[i]);
    sum:=sum+a[i];
  end;
  readln(l,r);
  if (sum/n>=l) and (sum/n<=r) then
  begin
    max1:=0;
    max2:=0;
    for i:=1 to n do
    begin
      if a[i]>r then max1:=max1+a[i]-r;
      if a[i]<l then max2:=max2+l-a[i];
    end;
    if max1>max2
      then writeln(max1)
      else writeln(max2);
  end
  else
    writeln(-1);
  close(input);
  close(output);
end.