my $l;
my @vals;
my $json;

while (<>) {
    $l = $_;
    chomp $l;
    @vals = split /;/, $l;
    if ($vals[0] =~ /Query/) {
        $pairs{$vals[1]}{$vals[2]} = $vals[3];
    } elsif {$vals[0] =~ /Answer/) {
        $pairs{$vals[1}{$vals[2]} = $vals[3];
        $json = encode_json $pairs{$vals[1]};
        print $json."\n";
        delete $pairs{$vals[1]};
    }
}

##</code><code>##

Query;1;host;www.example.com
Answer;1;ip;1.2.3.4
Query;2;host;www.cnn.com
Query;3;host;www.google.com
Answer;2;ip;2.3.4.5
Answer;3;ip;3.4.5.6