Thank you everyone, i some how able to solve this.

I did it by finding the count of unique A1's and i stored it in hash as a key, A loop to iterate that many number of times to create a new hash which store the A1 and activedate as a key.

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find the consecutive rows by having a count(unique A1 and B1).

In reply to Re^2: sorting and merging in perl by Sekhar Reddy
in thread sorting and merging in perl by Sekhar Reddy

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