It sounds like you might want to use grep:

my @array = (0,1,2,3,4,5);
@array = grep {$_ % 3} @array;  #replace $_%3 with whatever condition 
+applies.
print @array;
[download]

which returns "1245"

You can chop one element out with a splice:

my @array = (0,1,2,3,4,5);
my $cutme = <>;
@array = @array[0..$cutme-1, $cutme+1..$#array];
print @array;
[download]

Entering "2" gives "01345", "0" gives "12345", and so on. Of course, doing so changes the indices of some of the remaining elements, so be careful with this one.