Greetings

I need your help please..
I have a website of 20 pages. Each page displays an image from a catalog located in another domain, and the catalog changes each week, so I have to change the img src attribute each week too (the jpg images are named differently each week, though in the same directory). So instead of editing 20 html pages each time, I'm trying to find a way to control the img src from a text file, so that I edit only that text file once a week.

Is there a way to extract img src attributes from a text file or js file please?
For example I need page 1 to extract the first img src listed in the text file, and page 2 to extract the second src listed, etc.
I'm new to js so please give an example of the code that I should use.

Many thanks.