G'day phantom85,

This is very basic, so I suggest you first acquaint yourself with "perlintro" and the "perldoc Tutorials" (in particular, "perlfaq4").

The data you've provided isn't valid Perl; however, making an educated guess as to what it would really look like, let's say you start with data structures like this:

my $completed_courses = [...];
my $schedule = {...};
[download]

The first step would be to create a hash of completed courses. Something like this:

my %completed;

for (@$completed_courses) {
    $completed{$_->{title}} = undef;
}
[download]

Then, walk through the schedule and remove the completed ones. Something like this:

for (keys %$schedule) {
    delete $schedule->{$_} if exists $completed{$schedule->{$_}{Course
+}};
}
[download]

See also: delete and exists.

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