constant fn = open("mlijobs.txt", "r")
integer maxout = 0, jobnumber
sequence jobs = {}, maxtime, scanres
string inout, jobtime
object line
while 1 do
    line = gets(fn)
    if atom(line) then exit end if
    scanres = scanf(line,"License %s @ %s for job %d\n")
    if length(scanres)!=1 then
        printf(1,"error scanning line: %s\n",{line})
        {} = wait_key()
        abort(0)
    end if
    {{inout,jobtime,jobnumber}} = scanres
    if inout="OUT" then
        jobs &= jobnumber
        if length(jobs)>maxout then
            maxout = length(jobs)
            maxtime = {jobtime}
        elsif length(jobs)=maxout then
            maxtime = append(maxtime, jobtime)
        end if
    else
        jobs[find(jobnumber,jobs)] = jobs[$]
        jobs = jobs[1..$-1]
    end if
end while
close(fn)

printf(1, "Maximum simultaneous license use is %d at the following times:\n", maxout)
for i = 1 to length(maxtime) do
    printf(1, "%s\n", {maxtime[i]})
end for