awk zero pad last field in variable-length record

awk '{var = sprintf(NF); if (var == 4) printf "%s %s %s %026d\n" , $1,$2,$3,$4; else printf "%s %s %s %s %026d\n" , $1,$2,$3,$4,$5}' yourfilegoes.here >> yournewfilegoes.here
The sample output shows each record/row with the last field zero-padded to 26 digits. For testing, I used (L)ine and field/column numbers.... Line 4, field2 = L42, etc up to the last field where I just used line numbers X 4. I had some whitespace-delimited files with variable-length records/rows (having 4 - 5 fields/columns) which required reformatting by zero-padding the last field to 26 digits. This requires setting NF (Not $NF) as an awk variable, with a simple conditional that assumes that any line where (N)umber of (F)ields does NOT equal 4 has a NF of 5. If needed, more conditional checks can be added, and the "NF" changed to any field ($1, $5, etc).
Sample Output
L11 L12 L13 L14 00000000000000000000001111
L21 L22 L23 L24 00000000000000000000002222
L31 L32 L33 L34 00000000000000000000003333
L41 L42 L43 00000000000000000000004444
L51 L52 L53 00000000000000000000005555
L61 L62 L63 L64 00000000000000000000006666

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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