>, all neighbors of <strong>A</strong>, and so on, until every vertex in the graph has been visited.</p>
<p>(<span style="font-size: 10pt; background-color: #ffff99;"><em>Key take-away!</em></span>) The note highlighted above is a key take-away for BFS; failure to take note of that point is a common stumbling block and point of misunderstanding when people are asked identify valid breadth-first traversals through a graph. To reiterate: if we visit <strong>B</strong> before <strong>D</strong> in our BFS, we 