# Reads in lines of text until "quit" is read.
# Then prints duplicates, or prints "No duplicates seen."

my %lines; # holds lines of text encountered along with a count
           # of how many times it has been seen
my @dups;

while ( $_ = <> and $_ ne "quit\n" )
{
    $lines{$_}++; # increment value. if it dosn't exist yet, initializ
+es to 1
    if ( $lines{$_} == 2 ) # been seen before so add to dupes list
    {
        push @dups, $_;
    }
}

if ( @dups )
{
    print "Here are your duplicate lines:\n\n";
    foreach ( @dupes )
    {
        print;
    }
}
else
{
    print "No duplicates seen.\n";
}
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# prints out all the numbers from 1 to 100, along with any
# numbers they're evenly divisible by

for ( my $i = 1; $i <= 100; $i++ )
{
    print "$i: ";
    for ( my $j = 1; $j <= $i; $j++ )
    {
        if ( $i % $j == 0 )
        {
            print "$j ";
        }
    }
    print "\n";
}
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