/code> are not reference
parameters in the following function because they don't need to be.</p>

<div class="language-c++ good highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="cm">/* 
 * Solves a quadratic equation ax^2 + bx + c = 0,
 * storing the results in output parameters root1 and root2.
 * Assumes that the given equation has two real roots.
 */</span>
<span class="kt">void</span> <span class="nf">quadratic</span><span class="p">(</span><span class="kt">double</span