program my_1;

var
  a: array[1..100000] of longint;
  b, q, l, m, n, s, mount, ans, i, j, count, d: longint;

procedure swap(var a, b: longint);
var
  temp: longint;
begin
  temp := a;
  a := b;
  b := temp;
end;

procedure quicksort(l, r: longint);
var
  border, i: longint;
begin
  if l < r then begin
    border := l;
    for i := l to r - 1 do
      if (a[i] < a[r]) then begin
        swap(a[border], a[i]);
        inc(border);
      end;
    swap(a[border], a[r]);
    quicksort(l, border - 1);
    quicksort(border + 1, r);
  end;
end;

function binsrch(x: longint): boolean;
var
  l, r, i, j, k: longint;
  bool: boolean;
begin
  bool := false;
  l := 1;
  r := m;
  while (r - l > 1) and not bool do begin
    k := (r + l) div 2;
    if a[k] = abs(x) then bool := true;
    if a[k] > abs(x) then r := k
      else l := k;
  end;
  if (a[r] = x) or (a[l] = x) then bool := true;
  if bool then binsrch := true
    else binsrch := false;
end;

begin
  readln(b, q, l, m);
  for i := 1 to m do begin
    read(a[i]);
  end;
  count := 0;
  quicksort(1, m);
  if ((abs(q) = 1) or (b = 0)) and not binsrch(b) then writeln('inf')
    else if binsrch(b) and ((abs(q) = 1) or (b = 0)) then writeln(0)
    else begin
    while abs(b) < l do begin
      if not binsrch(b) then inc(count);
      b := b * q;
      if (d = b) and not binsrch(b) then begin
        writeln('inf');
        exit;
      end
        else if (d = b) and binsrch(b) then begin
          writeln(count);
          exit;
        end;
      d := b;
    end;
    writeln(count);
  end;
end.