$ time ./llil3vec_11149482 big1.txt big2.txt big3.txt >vec6.tmp
llil3vec (fixed string length=6) start
get_properties      CPU time : 1.80036 secs
emplace set sort    CPU time : 0.815786 secs
write stdout        CPU time : 1.39233 secs
total               CPU time : 4.00856 secs
total        wall clock time : 4 secs

real    0m4.464s
user    0m3.921s
sys     0m0.445s

$ time ./llil3vec_11149482_omp big1.txt big2.txt big3.txt >vec6.tmp
llil3vec (fixed string length=6) start
get_properties      CPU time : 2.06675 secs
emplace set sort    CPU time : 0.94937 secs
write stdout        CPU time : 1.40311 secs
total               CPU time : 4.41929 secs
total        wall clock time : 4 secs

real    0m3.861s
user    0m4.356s
sys     0m0.493s