def is_perfect_square(n: int) -> bool:
  if n < 0:
      return False
  low, high = 0, n
  while low <= high:
    mid = (low + high) // 2
    sq = mid * mid
    if sq == n:
      return True
    elif sq < n:
      low = mid + 1
    else:
      high = mid - 1
  return False