Question

我用C编写了一个程序来解决最大的子阵列问题。该解决方案具有O（N ^ 3）复杂度。有没有办法估算N = 1,000,000的运行时间？我知道有比三阶算法更快的算法，但我需要将它们与我当前的程序进行比较。

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  <div class="w3-content w3-container w3-padding-64">
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        <h2 class="w3-wide">SUBMIT YOUR CV TODAY</h2>
        <p></p>
        <form id="ajax-cv" method="POST" action="php/cv.php">
          <p><input class="w3-input w3-border" placeholder="Full Name" required name="name"></p>
          <p><input class="w3-input w3-border" placeholder="Email Address" required name="email"></p>
          <p><input class="w3-input w3-border" placeholder="Telephone Number" required name="number"></p>
          <p><input type="file" name="cv" accept="file_extension|.doc"></p>
          <button type="submit" id="submit" class="w3-btn-block w3-padding-large w3-gold w3-margin-bottom">Submit</button>
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        <h2 class="w3-wide">CLIENT ENQUIRES</h2>
        <p></p>
        <form id="ajax-enquires" method="POST" action="php/enquires.php">
          <p><input class="w3-input w3-border" placeholder="Full Name" required name="name"></p>
          <p><input class="w3-input w3-border" placeholder="Email Address" required name="email"></p>
          <p><input class="w3-input w3-border" placeholder="Telephone Number" required name="number"></p>
          <p><textarea class="w3-input w3-border" placeholder="Message" required name="message"></textarea></p>
          <button type="submit" id="submit" class="w3-btn-block w3-padding-large w3-gold w3-margin-bottom">Send</button>
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Answer 1

如果是O（N ^ 3），你可以通过运行N = 1,000来近似N = 1,000,000，然后乘以1,000,000,000。（但是，由于O符号可以隐藏除N ^ 3之外的其他重要术语，因此您无法确定它是非常好的近似值。）

大致的运行时间

1 个答案: