I have 2 text files file "A" has about 1000 lines. File "B" has more than 100,000 lines (size about 5mega). Contents of file "A" is something like the following -Comes in pairs (2 lines) every 2 lines is a pair in my explanation
abc
123
cfg
12345
fghh
1aaaaa
Missing in file "B" is each pairs first line - I want to insert into file "B" (or create third file-might be even better!) missing line above matching second line. Pls note lines may appear many times. I tried and have a very "newbie file" (not for all to see) which works but takes more than an hour to finish due to brute-force loop I use!! Thanx

In reply to Insert row from file by smbs

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