gobyexample/public/recursion
Mark McGranaghan 78e1fd61ec Clean up merge
2019-09-01 16:09:36 -07:00

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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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<a href="http://play.golang.org/p/4yUp5wLVyiG"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
<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>
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<div class="highlight"><pre><span class="gp">$</span> go run recursion.go
<span class="go">5040</span>
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Next example: <a href="pointers">Pointers</a>.
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by <a href="https://markmcgranaghan.com">Mark McGranaghan</a> | <a href="https://github.com/mmcgrana/gobyexample/blob/master/examples/recursion">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
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