awk - add column of 1's to tab-delimited file -

can't find solution, though thousands of variations of question have been asked.

i want add column of 1's tab-delimited file using awk or sed.

the file have 20 million lines, efficient nice.

turn this:

a   b   c r   j   k   t   w

into this:

a   b   c   1 r   j   k   1   t   w   1

assuming used awk -f'\t' instead of awk:

{     print $0 fs 1; }

if didn't use -f option, replace fs 1 "\t1".

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