How to publish a two-dimensional array msg with int8 type?

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I now have a two-dimensional array of size nxn where n < 10 with int8 or int16 type array elements. I need to publish this array to a topic. I defined my own msg header, a simple int8 type msg such as the following:

int8 num

Can I do something like this: Let's say A is a two-dimensional array A = [1 2; 1 3];

ros::Publisher pub = n.advertise<test1::int8>("Chatter", 1000);
pub.publish(A);

In the callback function of the subscriber:

void chatterCallback(const test1::num& msg)
{
    ROS_INFO(...);
}

Is there any problem with this approach?