my $size = @array;

for (my $i=1; $i < @array; $i++)    {

    if (($array[$i] <0)  &&  ($array[$i-1] > 0))   {

                 push @found, "$array[$i-1] $array[1]";
                 # want to get from $i+1 to end of array
                 # tried: push @rest, "$array[$i+1] .. $array[$size]";
    }

}