I have two patent forms. What function can be used to quickly find out whether there are duplicate patent numbers in these two tables for statistics? Thank you.

Copy them into an Excel table first (if you need to separate them in the end, you can fill them with different colors to avoid confusion), select the column of the application number, start-conditional format-highlight cell rule-duplicate value, and then a small dialog box will pop up, with the content that the duplicate value is set to light red and filled with dark red font, and click Default. Then you will see that the repeated places are marked with light red fillers, and I don't need to say the rest.