Any of the "sliding window" approaches will answer your question. However, I suspect that you have an XY Problem. If you describe what you need to count, we may be able to suggest a better algorithm. My best guess is that you want the number of distinct values for the first field in your data. Can you be sure that like values are always consecutive?
Bill

In reply to Re: Dealing with nextline of a file by BillKSmith
in thread Dealing with nextline of a file by jnarayan81

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