UNIX for Dummies Questions & Answers

There is a file:

!EN
ih
n
w
ey


I want to join the current instance with its previous instance together, such as: previous_instance-B+current_instance, there "-B+" is fixed iterm, the file after operate look like:

!EN start-B+!EN
ih !EN-B+ih
n ih-B+n
w n-B+w
ey w-B+ey

what I think is we can use command
awk ' {being="start";$2=${begin}-B+$1;print;begin=$1;next}' <filename > newfilename

but it does not work.

what command should I use? Thanks in advance

Try...

Code:

$ cat file1
!EN
ih
n
w
ey

$ awk 'BEGIN{b="start"}{$2=b "-B+" $1;print;b=$1}' file1 > file2

$ cat file2
!EN start-B+!EN
ih !EN-B+ih
n ih-B+n
w n-B+w
ey w-B+ey