match index notation of file1 to the index of file2 and pull out matching rows

Question

file1 contains multiple alphabetic sequences:

AETYUIOOILAKSJ
EAYEURIOPOSIDK
RYXURIAJSKDMAO
URITORIEJAHSJD
YWQIAKSJDHFKCM
HAJSUDIDSJSIAJ
AJDHDPFDIXSIBJ
JAQIAUXCNC         


        

Answer 1

With GNU awk and grep:

awk -v FPAT='[0-9]+|[A-Z]+' '{ print "^.{" $1-1 "}" $2 }' file1 | grep -Ef - file2

Output:

AETYUIOOILAKSJ
RYXURIAJSKDMAO
URITORIEJAHSJD
JAQIAUXCNCVUFO