Click two game object

Scripting
1

I ask simple things

I got 2 Cube

I can click first cup with Onmousedrag script
but I want :
if ı click second cube before first cube game must give error

I try use Onmousedrag statement with if but I already got error

How can I Do that (with c#sharp)

2

You want to check the order in which the two objects were clicked? You can have a bool on each object that signifies the order of it’s click, and compare it. Check when you click the second object, if the first object bool is true or not. If not, throw an error.

3

I show examp
Void OnMouseDrag (){

if (I want write this here=if I click first cube=true if I click second cube before first cube game give error );

}