def get_accuracy(Y, Y_pred):
    """
    Calcualtes accuracy.

    :param Y: int(N, )
        Correct labels.
    :param Y_pred: int(N, ) | double(N, C)
        Predicted labels of shape(N, ) or (N, C) in case of one-hot vector.
    :return: double
        Accuracy.
    """
    return (Y == Y_pred).mean()
    # return (np.argmax(Y, axis=1) == Y_pred).mean() #used in case of one-hot vector and loss is Negative Likelihood.