How to read many input files in AWK? -

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• awk: extract different columns many different files 3 answers

i try understand how read many input files in awk puzzle "how can print 1st column file 1 , 2nd column file 2?

input

$ cat test1  1   4 2   5 3   6 $ cat test2   b c   d    e   f 

goal

$ awk **answer** 1   b 2   d 3   f 

awk 'nr==fnr{a[nr]=$1;next} {print a[fnr], $2}' file1 file2