Publishing multiple variables using a single publisher

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I have written a publisher to publish a float32 value to a topic depth_m. Now, I need to publish two more variables and they are of type int, not float. I would like all three of these variables to be published to the same topic. I am referring to the official tutorial). Do I just replace Float32 in the following lines with Int32 and add it to the existing publisher?

ros::Publisher depth_pub = pub_.advertise<std_msgs::Float32>("depth_m", 1000);
std_msgs::Float32 msg;

I believe I will have to edit msg to a different variable name msg1, msg2. According to me the whole thing will have the following lines:

ros::Publisher depth_pub = pub_.advertise<std_msgs::Float32>("depth_m", 1000);
ros::Publisher depth_pub2 = pub_.advertise<std_msgs::Int32>("depth_m", 1000);

std_msgs::Float32 msg;
std_msgs::Int32 msg1;
std_msgs::Int32 msg2;    

msg.data=depth;
msg1.data=var1;
msg2.data=var2;

depth_pub.publish(msg); 
depth_pub2.publish(msg1);
depth_pub2.publish(msg2);

Is this the right strategy? If do this, will the whole thing act as a single message or multiple messages? Can I avoid two advertise lines by using just std_msgs instead of std_msgs::Float32?