def acc_score(y_true, y_pred):
    """
    Calculate accuracy for the given predictions vector
    """
    cnt_matches = 0
    if len(y_true) == 0:
        return cnt_matches
    for true, pred in zip(y_true, y_pred):
        if true == pred:
            cnt_matches += 1
    return cnt_matches / len(y_true)