122 lines
9.1 KiB
HTML
122 lines
9.1 KiB
HTML
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</style><!-- hexo-inject:begin --><!-- hexo-inject:end --></head><body><header><a href="/" class="logo-link"><img src="/logo.png"></a><ul class="nav nav-list"><li class="nav-list-item"><a href="/" target="_self" class="nav-list-link">ALL</a></li><li class="nav-list-item"><a href="/categories/leetcode/" target="_self" class="nav-list-link">LEETCODE</a></li><li class="nav-list-item"><a href="https://bearmiebear.blogspot.com" target="_blank" class="nav-list-link">BEAR</a></li><li class="nav-list-item"><a href="/atom.xml" target="_self" class="nav-list-link">RSS</a></li></ul></header><section class="container"><div class="post"><article class="post-block"><h1 class="post-title">leetcode-225</h1><div class="post-meta"><div class="post-time">2020年3月23日</div></div><div class="post-content"><h3 id="225-__u7528_u961F_u5217_u5B9E_u73B0_u6808"><a href="#225-__u7528_u961F_u5217_u5B9E_u73B0_u6808" class="headerlink" title="225. 用队列实现栈"></a>225. 用队列实现栈</h3><p><a href="https://leetcode-cn.com/problems/implement-stack-using-queues/" target="_blank" rel="noopener">题目</a></p>
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<!-- hexo-inject:begin --><!-- hexo-inject:end --><a id="more"></a>
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<p>注意栈是 FILO(First In Last Out)，Python 的 list 是 FIFO(First In First Out)。</p>
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<figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br></pre></td><td class="code"><pre><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">MyStack</span>:</span></span><br><span class="line"></span><br><span class="line"> <span class="function"><span class="keyword">def</span> <span class="title">__init__</span><span class="params">(self)</span>:</span></span><br><span class="line"> <span class="string">"""</span></span><br><span class="line"><span class="string"> Initialize your data structure here.</span></span><br><span class="line"><span class="string"> """</span></span><br><span class="line"> self.data = []</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"> <span class="function"><span class="keyword">def</span> <span class="title">push</span><span class="params">(self, x: int)</span> -> <span class="keyword">None</span>:</span></span><br><span class="line"> <span class="string">"""</span></span><br><span class="line"><span class="string"> Push element x onto stack.</span></span><br><span class="line"><span class="string"> """</span></span><br><span class="line"> self.data.append(x)</span><br><span class="line"> <span class="keyword">return</span></span><br><span class="line"></span><br><span class="line"></span><br><span class="line"> <span class="function"><span class="keyword">def</span> <span class="title">pop</span><span class="params">(self)</span> -> int:</span></span><br><span class="line"> <span class="string">"""</span></span><br><span class="line"><span class="string"> Removes the element on top of the stack and returns that element.</span></span><br><span class="line"><span class="string"> """</span></span><br><span class="line"> <span class="keyword">return</span> self.data.pop(<span class="number">-1</span>)</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"> <span class="function"><span class="keyword">def</span> <span class="title">top</span><span class="params">(self)</span> -> int:</span></span><br><span class="line"> <span class="string">"""</span></span><br><span class="line"><span class="string"> Get the top element.</span></span><br><span class="line"><span class="string"> """</span></span><br><span class="line"> <span class="keyword">return</span> self.data[<span class="number">-1</span>]</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"> <span class="function"><span class="keyword">def</span> <span class="title">empty</span><span class="params">(self)</span> -> bool:</span></span><br><span class="line"> <span class="string">"""</span></span><br><span class="line"><span class="string"> Returns whether the stack is empty.</span></span><br><span class="line"><span class="string"> """</span></span><br><span class="line"> <span class="keyword">return</span> <span class="keyword">not</span> bool(self.data)</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"></span><br><span class="line"><span class="comment"># Your MyStack object will be instantiated and called as such:</span></span><br><span class="line"><span class="comment"># obj = MyStack()</span></span><br><span class="line"><span class="comment"># obj.push(x)</span></span><br><span class="line"><span class="comment"># param_2 = obj.pop()</span></span><br><span class="line"><span class="comment"># param_3 = obj.top()</span></span><br><span class="line"><span class="comment"># param_4 = obj.empty()</span></span><br><span class="line"></span><br><span class="line"><span class="comment">#24 ms 13.5 MB</span></span><br></pre></td></tr></table></figure>
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</div></article></div></section><footer><div class="paginator"><a href="/2020/03/25/leetcode-543/" class="prev">PRVE</a><a href="/2020/03/23/leetcode-169/" class="next">NEXT</a></div><div class="copyright"><p>© 2016 - 2020 <a href="http://blog.tunpok.com">Ching</a>, unless otherwise noted.</p></div></footer><script src="https://cdn.bootcss.com/mathjax/2.5.3/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script><!-- hexo-inject:begin --><!-- hexo-inject:end --></body></html> |