How do I condense my code for my triggers?

Hi Everyone, I'm here again :)

I have a trigger outside each door so when I collide with it it shows the room number and says press C to open the only problem is I have a different script for each door so it shows I different room number.

My code is below, I just what to know how I would compress it down to a single script if possible.

 var displayMessage = false;
 var font : Font;
 var fontSize : int = 20;
 
 function OnTriggerEnter (other : Collider) {
     displayMessage = true;
 }
 
 function OnGUI () {
 if (displayMessage){
     GUI.Label (Rect (10, 10, 200, 60), "Room 2\nPress C To Open");
     GUI.skin.label.font = GUI.skin.button.font = GUI.skin.box.font = font;
     GUI.skin.label.fontSize = GUI.skin.box.fontSize = GUI.skin.button.fontSize = fontSize;
     }
 }
     
 function OnTriggerExit (other : Collider) {
     displayMessage = false;
 }