Dynamically calling movie clip instance

Hi there,

I’m trying to reference an instance of a movie clip without using the exact name. This is hard to explain so I’ll give you the example:

I have 6 movie clips: (mc_movie1, mc_movie2, mc_movie3…etc)
I also have 6 buttons. when I press button two for example variable ‘button_pressed’ is set to 2.

Now, I’m trying to affect the movie clips depending on which button is pressed.

so what I want to know is how to write, for example : mc_movie(button_pressed)._x =100;
…where the (button pressed) value will mean this action will affect mc_movie2
if it was a string it c would be: “this is string number” + button_pressed +" of 6"… so how can i achieve this when it’s an instance name?

very hard to explain, hope you guys understand and can help!!
cheers:)