lass="r-pr">#&gt;</span>  [4,] ""   ""   "r"  "r"  "u"  ""   "r"  "r"  "d" </span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  [5,] ""   ""   ""   ""   ""   ""   ""   ""   "d" </span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  [6,] ""   ""   "d"  "l"  "l"  ""   "d"  "l"  "l" </span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  [7,] ""   ""   "d"  ""   "u"  ""   "d"  ""   ""  </span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  [8,] "d"  "l"  "l"  ""   "u"  "l" 