ass="keyword">virtual</span> <span class="keywordtype">double</span> next_transition_cost(<span class="keywordtype">size_t</span> i,
<a name="l00268"></a>00268                                       <span class="keywordtype">size_t</span> j, <span class="keywordtype">size_t</span> k) <span class="keyword">const</span> = 0;
<a name="l00269"></a>00269 
<a name="l00270"></a>00270   <span class="comment">// return transition cost of [j-th tag at i-th token] to</span>
<a name="l00271"></a>00271   <span class="com