def calculate_strong_beats(beats_in_bar, grouping):
    """
    Given a particular number of beats in a bar and grouping option, we need to calculate what
    beats are to be considered strong beats. for example in 7/4 time signature, with grouping of
    2,2,3 the strong beats are 1, 3, and 5.
    
    :param beats_in_bar: integer. The number of beats in a bar.
    :param grouping: list of integers. The beat grouping chosen by the user.
    """
    strong_beats = [1]
    for beat in grouping:
        strong_beat = strong_beats[-1] + (beat)
        if strong_beat < beats_in_bar:
            strong_beats.append(strong_beat)
    return strong_beats