def METHOD_NAME(num: int) -> int:
    """
    Efficiently computes sqrt for integer values
    Dropin replacement for python3.8's isqrt function
    Credits : https://stackoverflow.com/a/53983683
    Parameters
    ----------
    num : int, input
    Returns
    -------
    sqrt_num : int, rounded down sqrt of num
    Notes
    -----
    - Doesn't handle edge-cases of negative numbers by design
    - Doesn't type-check for integers by design, although it is hinted at
    Examples
    --------
    """
    if num > 0:
        x_iterate = 1 << (num.bit_length() + 1 >> 1)
        while True:
            f_iterate = (x_iterate + num // x_iterate) >> 1
            if f_iterate >= x_iterate:
                return x_iterate
            x_iterate = f_iterate
    elif num == 0:
        return 0