> ./llil2vec big1.txt big2.txt big3.txt >f.tmp
llil2vec start
get_properties      CPU time : 3.06708 secs
emplace set sort    CPU time : 0.903617 secs
write stdout        CPU time : 1.23459 secs
total               CPU time : 5.20544 secs
total        wall clock time : 5 secs

> ./llil2vec big1.txt big2.txt big3.txt >f.tmp
llil2vec start
get_properties      CPU time : 3.4832 secs
emplace set sort    CPU time : 1.10209 secs
write stdout        CPU time : 0.939805 secs
total               CPU time : 5.52519 secs
total        wall clock time : 6 secs

> ./llil2vec big1.txt big2.txt big3.txt >f.tmp
llil2vec start
get_properties      CPU time : 3.42605 secs
emplace set sort    CPU time : 0.916222 secs
write stdout        CPU time : 1.00049 secs
total               CPU time : 5.343 secs
total        wall clock time : 5 secs

> diff f.tmp vec.tmp