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<h1>Examples</h1>
<p class="para">
<div class="example" id="example-3398">
<p><strong>Example #1 Factorial function using GMP</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #007700">function </span><span style="color: #0000BB">fact</span><span style="color: #007700">(</span><span style="color: #0000BB">$x</span><span style="color: #007700">) <br />{<br /> </span><span style="color: #0000BB">$return </span><span style="color: #007700">= </span><span style="color: #0000BB">1</span><span style="color: #007700">;<br /> for (</span><span style="color: #0000BB">$i</span><span style="color: #007700">=</span><span style="color: #0000BB">2</span><span style="color: #007700">; </span><span style="color: #0000BB">$i </span><span style="color: #007700"><= </span><span style="color: #0000BB">$x</span><span style="color: #007700">; </span><span style="color: #0000BB">$i</span><span style="color: #007700">++) {<br /> </span><span style="color: #0000BB">$return </span><span style="color: #007700">= </span><span style="color: #0000BB">gmp_mul</span><span style="color: #007700">(</span><span style="color: #0000BB">$return</span><span style="color: #007700">, </span><span style="color: #0000BB">$i</span><span style="color: #007700">);<br /> }<br /> return </span><span style="color: #0000BB">$return</span><span style="color: #007700">;<br />}<br /><br />echo </span><span style="color: #0000BB">gmp_strval</span><span style="color: #007700">(</span><span style="color: #0000BB">fact</span><span style="color: #007700">(</span><span style="color: #0000BB">1000</span><span style="color: #007700">)) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">?></span>
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</code></div>
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<p class="para">
This will calculate factorial of 1000 (pretty big number)
very fast.
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