Thank you for your answer. The problem is that I've a big file (40000 line), that's why I did'nt bring it to my post. and also I can't specify all the wanted lines, I just want to check if for every line there is another line witch have the same first word then I check it to delete one of them, that's why I did two loops. but the algorithm is so slow

In reply to Re^4: How to check lines that start with the same word then delete one of them by agnes00
in thread How to check lines that start with the same word then delete one of them by agnes00

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