recursion

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      <h2><a href="./">Go by Example</a>: Recursion</h2>

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            <p>Go supports
<a href="http://en.wikipedia.org/wiki/Recursion_(computer_science)"><em>recursive functions</em></a>.
Here&rsquo;s a classic factorial example.</p>

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            <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
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            <div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
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            <p>This <code>fact</code> function calls itself until it reaches the
base case of <code>fact(0)</code>.</p>

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            <div class="highlight"><pre><span class="kd">func</span> <span class="nx">fact</span><span class="p">(</span><span class="nx">n</span> <span class="kt">int</span><span class="p">)</span> <span class="kt">int</span> <span class="p">{</span>
    <span class="k">if</span> <span class="nx">n</span> <span class="o">==</span> <span class="mi">0</span> <span class="p">{</span>
        <span class="k">return</span> <span class="mi">1</span>
    <span class="p">}</span>
    <span class="k">return</span> <span class="nx">n</span> <span class="o">*</span> <span class="nx">fact</span><span class="p">(</span><span class="nx">n</span><span class="o">-</span><span class="mi">1</span><span class="p">)</span>
<span class="p">}</span>
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            <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">fact</span><span class="p">(</span><span class="mi">7</span><span class="p">))</span>
<span class="p">}</span>
</pre></div>

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            <div class="highlight"><pre><span class="gp">$</span> go run recursion.go
<span class="go">5040</span>
</pre></div>

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