 of the issues. A run with our time complexity analysis functions <code>asymptoticTimings</code> and <code>asymptoticTimeComplexityClass</code> with suitable parameters show that both substring and gregexpr yield linear time complexity:</p>
<div class="sourceCode" id="cb1"><html><body><pre class="r"><span class="fu"><a href="https://rdrr.io/r/base/library.html">library</a></span>(<span class="no">testComplexity</span>)
<span class="co"># substring function test:</span>
<span class="fu"><a href="../reference