div class=content><div>一行两个正整数，分别表示n和m。</div>
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<div>n&lt;=50,m&lt;=8</div>
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<p></p></div></div></div></div></div><div class="row"><div class="column"><h4 class="ui top attached block header">输出格式</h4><div class="ui bottom attached segment font-content"><div style="position: relative; overflow: hidden;"><div class=content><div>一行一个正整数表示答案。</div>
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