#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;

my $aref = [6, 1, 7, 6, 2, 2, 7, 1, 6, 99, 99, 7, 88, 7, 6, 1, 2, 3];
my (@temp, @result);
my $flag = 0;

for my $num (@$aref) {
    $flag = 1 if $num == 6;
    if ($flag) {
        push @temp, $num;
    } else {
        push @result, $num;
    }
    if ($num == 7) {
        @temp = ();
        $flag = 0;
    } 
}
push @result, @temp;
print Dumper \@result;