def get_peaks(mmr_size) -> List[int]:
    """
    return peaks positions from left to right
    """
    def get_right_peak(height, pos, mmr_size):
        """
        find next right peak
        peak not exsits if height is -1
        """
        # jump to right sibling
        pos += sibling_offset(height)
        # jump to left child
        while pos > mmr_size - 1:
            height -= 1
            if height < 0:
                # no right peak exists
                return (height, None)
            pos -= 2 << height
        return (height, pos)

    poss = []
    height, pos = left_peak_height_pos(mmr_size)
    poss.append(pos)
    while height > 0:
        height, pos = get_right_peak(height, pos, mmr_size)
        if height >= 0:
            poss.append(pos)
    return poss