@f = <>;
for (1..shift(@f)) {
    @s=();
    for (1 .. shift(@f)) {
        @l = split ' ', shift @f;
        $i=0;
        $y=0;
        for (@l) {
            $x = $y;
            $y = $s[$i++];
            $_ += $x > $y ? $x : $y;
        }
        @s = @l;
    }
    $m = 0;
    $m = $m > $_ ? $m : $_ for @s;
    print "$m\n";
}