<p>Given a collection of candidate numbers (<code>candidates</code>) and a target number (<code>target</code>), find all unique combinations in <code>candidates</code> where the candidate numbers sum to <code>target</code>.</p>
<p>Each number in <code>candidates</code> may only be used <strong>once</strong> in the combination.</p>
<p><strong>Note:</strong> The solution set must not contain duplicate combinations.</p>