Hey,
Can anyone tell me what is test 28?? I have time limit exceeded?

This is my code:
program Monobilliards_1494;

var
  tmp, b, a, i, n: LongInt;
  x: array [1..100000] of LongInt;
  cheater: boolean;

begin
  cheater := false;
  readln(n);
  for i := 1 to n do readln(x[i]);

  i := 1;
  tmp := x[1] - 1;
  while (i <= n) and not cheater do begin
    if tmp < x[i] then begin
      b := x[i] - i;
      tmp := x[i];
      a := i + 1;
      while (a <= n) and (b > 0) do begin
        if tmp > x[a] then begin
          b := b - 1;
          tmp := x[a];
        end;
        a := a + 1;
      end;
    end;
    tmp := x[i];
    if b > 0 then cheater := true;
    i := i + 1;
  end;

  if cheater then writeln('Cheater')
  else writeln('Not a proof');
end.