Hello Monks,
I came across this below piece of code during my search for finding missing elements from a list of numbers.
However I find it a little hard to understand and would like some help in understanding this piece of code.
I found this code in a thread in this site Finding missing numbers in a list. 


@idslist;  ##contains a list of id numbers 

print "Total element in idslist = $#idslist\n";

push @missing_ids, $idslist[ $_ ] +1 .. $idslist[ $_+1 ] -1 for 0 .. $
+#idslist-1;

print "Total element in missing_ids_list = $#missing_ids\n";

[download]

The most puzzling thing when i executed this code was below

Total element in idslist = 8436
Total element in missing_ids_list = 77502867

I was expecting missing_ids_list to have less elements than idslist since the loop goes only through this number.

In reply to Understanding this code by aaron.schweitzer

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