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class="sidebar-link">The Contributors</a></li></ul></section></li></ul> </aside> <main class="page"> <div class="theme-default-content content__default"><h1 id="refactoring-techniques"><a href="#refactoring-techniques" class="header-anchor">#</a> Refactoring Techniques</h1> <p><strong>Refactoring</strong> refers to the modification of existing code into an improved version. Although refactoring is often done while changing code to add features or fix bugs, the term particularly refers improving code without necessarily adding features or fixing bugs.</p> <h2 id="goto-cleanup"><a href="#goto-cleanup" class="header-anchor">#</a> Goto Cleanup</h2> <p>In C++ code bases which used to be C, one can find the pattern <code>goto cleanup</code>. As the <code>goto</code> command makes the workflow of a function harder to understand, this is often avoided. Often, it can be replaced by return statements, loops, functions. Though, with the <code>goto cleanup</code> one needs to get rid of cleanup logic.</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code><span class="token keyword">short</span> <span class="token function">calculate</span><span class="token punctuation">(</span>VectorStr <span class="token operator">*</span><span class="token operator">*</span>data<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">short</span> result <span class="token operator">=</span> FALSE<span class="token punctuation">;</span>
VectorStr <span class="token operator">*</span>vec <span class="token operator">=</span> <span class="token constant">NULL</span><span class="token punctuation">;</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>data<span class="token punctuation">)</span>
<span class="token keyword">goto</span> cleanup<span class="token punctuation">;</span> <span class="token comment">//< Could become return false</span>
<span class="token comment">// ... Calculation which 'new's VectorStr</span>
result <span class="token operator">=</span> TRUE<span class="token punctuation">;</span>
cleanup<span class="token operator">:</span>
<span class="token keyword">delete</span> <span class="token punctuation">[</span><span class="token punctuation">]</span> vec<span class="token punctuation">;</span>
<span class="token keyword">return</span> result<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>In C++ one could use <a href="https://stackoverflow.com/documentation/c%2b%2b/1320/raii-resource-acquisition-is-initialization" target="_blank" rel="noopener noreferrer">RAII<span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a> to fix this issue:</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code><span class="token keyword">struct</span> <span class="token class-name">VectorRAII</span> <span class="token keyword">final</span> <span class="token punctuation">{</span>
VectorStr <span class="token operator">*</span>data<span class="token punctuation">{</span><span class="token keyword">nullptr</span><span class="token punctuation">}</span><span class="token punctuation">;</span>
<span class="token function">VectorRAII</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=</span> <span class="token keyword">default</span><span class="token punctuation">;</span>
<span class="token operator">~</span><span class="token function">VectorRAII</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">delete</span> <span class="token punctuation">[</span><span class="token punctuation">]</span> data<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token function">VectorRAII</span><span class="token punctuation">(</span><span class="token keyword">const</span> VectorRAII <span class="token operator">&</span><span class="token punctuation">)</span> <span class="token operator">=</span> <span class="token keyword">delete</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span><span class="token punctuation">;</span>
<span class="token keyword">short</span> <span class="token function">calculate</span><span class="token punctuation">(</span>VectorStr <span class="token operator">*</span><span class="token operator">*</span>data<span class="token punctuation">)</span> <span class="token punctuation">{</span>
VectorRAII vec<span class="token punctuation">{</span><span class="token punctuation">}</span><span class="token punctuation">;</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>data<span class="token punctuation">)</span>
<span class="token keyword">return</span> FALSE<span class="token punctuation">;</span> <span class="token comment">//< Could become return false</span>
<span class="token comment">// ... Calculation which 'new's VectorStr and stores it in vec.data</span>
<span class="token keyword">return</span> TRUE<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>From this point on, one could continue refactoring the actual code. For example by replacing the <code>VectorRAII</code> by <code>std::unique_ptr</code> or <code>std::vector</code>.</p> <h2 id="refactoring-walk-through"><a href="#refactoring-walk-through" class="header-anchor">#</a> Refactoring walk through</h2> <p>Here's a program which might benefit from refactoring. It's a simple program using C++11 which is intended to calculate and print all prime numbers from 1 to 100 and is based on a program that was posted on <a href="https://codereview.stackexchange.com/" target="_blank" rel="noopener noreferrer">CodeReview<span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a> for review.</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code><span class="token macro property"><span class="token directive-hash">#</span><span class="token directive keyword">include</span> <span class="token string"><iostream></span></span>
<span class="token macro property"><span class="token directive-hash">#</span><span class="token directive keyword">include</span> <span class="token string"><vector></span></span>
<span class="token macro property"><span class="token directive-hash">#</span><span class="token directive keyword">include</span> <span class="token string"><cmath></span></span>
<span class="token keyword">int</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">int</span> l <span class="token operator">=</span> <span class="token number">100</span><span class="token punctuation">;</span>
<span class="token keyword">bool</span> isprime<span class="token punctuation">;</span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> primes<span class="token punctuation">;</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> no <span class="token operator">=</span> <span class="token number">3</span><span class="token punctuation">;</span> no <span class="token operator"><</span> l<span class="token punctuation">;</span> no <span class="token operator">+=</span> <span class="token number">2</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">=</span> <span class="token boolean">true</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> primecount<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator"><=</span> std<span class="token double-colon punctuation">::</span><span class="token function">sqrt</span><span class="token punctuation">(</span>no<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token operator">++</span>primecount<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>no <span class="token operator">%</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">==</span> <span class="token number">0</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">=</span> <span class="token boolean">false</span><span class="token punctuation">;</span>
<span class="token keyword">break</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token keyword">if</span> <span class="token punctuation">(</span>primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">*</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">></span> no<span class="token punctuation">)</span> <span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> no <span class="token operator"><<</span> <span class="token string">"\n"</span><span class="token punctuation">;</span>
<span class="token keyword">break</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>isprime<span class="token punctuation">)</span> <span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> no <span class="token operator"><<</span> <span class="token string">" "</span><span class="token punctuation">;</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span>no<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> <span class="token string">"\n"</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>The output from this program looks like this:</p> <blockquote></blockquote> <p>3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97</p> <p>The first thing we notice is that the program fails to print <code>2</code> which is a prime number. We could simply add a line of code to simply print that one constant without modifying the rest of the program, but it might be neater to <strong>refactor</strong> the program to split it into two parts - one that creates the prime number list an another that prints them. Here's how that might look:</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code><span class="token macro property"><span class="token directive-hash">#</span><span class="token directive keyword">include</span> <span class="token string"><iostream></span></span>
<span class="token macro property"><span class="token directive-hash">#</span><span class="token directive keyword">include</span> <span class="token string"><vector></span></span>
<span class="token macro property"><span class="token directive-hash">#</span><span class="token directive keyword">include</span> <span class="token string"><cmath></span></span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> <span class="token function">prime_list</span><span class="token punctuation">(</span><span class="token keyword">int</span> limit<span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">bool</span> isprime<span class="token punctuation">;</span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> primes<span class="token punctuation">;</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> no <span class="token operator">=</span> <span class="token number">3</span><span class="token punctuation">;</span> no <span class="token operator"><</span> limit<span class="token punctuation">;</span> no <span class="token operator">+=</span> <span class="token number">2</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">=</span> <span class="token boolean">true</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> primecount<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator"><=</span> std<span class="token double-colon punctuation">::</span><span class="token function">sqrt</span><span class="token punctuation">(</span>no<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token operator">++</span>primecount<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>no <span class="token operator">%</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">==</span> <span class="token number">0</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">=</span> <span class="token boolean">false</span><span class="token punctuation">;</span>
<span class="token keyword">break</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token keyword">if</span> <span class="token punctuation">(</span>primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">*</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">></span> no<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">break</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>isprime<span class="token punctuation">)</span> <span class="token punctuation">{</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span>no<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> primes<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">int</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> primes <span class="token operator">=</span> <span class="token function">prime_list</span><span class="token punctuation">(</span><span class="token number">100</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span>std<span class="token double-colon punctuation">::</span>size_t i <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span> i <span class="token operator"><</span> primes<span class="token punctuation">.</span><span class="token function">size</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token operator">++</span>i<span class="token punctuation">)</span> <span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> primes<span class="token punctuation">[</span>i<span class="token punctuation">]</span> <span class="token operator"><<</span> <span class="token string">' '</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> <span class="token string">'\n'</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>Trying this version, we see that it does indeed work correctly now:</p> <blockquote></blockquote> <p>2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97</p> <p>The next step is to notice that the second <code>if</code> clause is not really needed. The logic in the loop looks for prime factors of each given number up to the square root of that number. This works because if there are any prime factors of a number at least one of them must be less than or equal to the square root of that number. Reworking just that function (the rest of the program remains the same) we get this result:</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code>std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> <span class="token function">prime_list</span><span class="token punctuation">(</span><span class="token keyword">int</span> limit<span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">bool</span> isprime<span class="token punctuation">;</span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> primes<span class="token punctuation">;</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> no <span class="token operator">=</span> <span class="token number">3</span><span class="token punctuation">;</span> no <span class="token operator"><</span> limit<span class="token punctuation">;</span> no <span class="token operator">+=</span> <span class="token number">2</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">=</span> <span class="token boolean">true</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> primecount<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator"><=</span> std<span class="token double-colon punctuation">::</span><span class="token function">sqrt</span><span class="token punctuation">(</span>no<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token operator">++</span>primecount<span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>no <span class="token operator">%</span> primes<span class="token punctuation">[</span>primecount<span class="token punctuation">]</span> <span class="token operator">==</span> <span class="token number">0</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">=</span> <span class="token boolean">false</span><span class="token punctuation">;</span>
<span class="token keyword">break</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>isprime<span class="token punctuation">)</span> <span class="token punctuation">{</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span>no<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> primes<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>We can go further, changing variable names to be a bit more descriptive. For example <code>primecount</code> isn't really a count of primes. Instead it's an index variable into the vector of known primes. Also, while <code>no</code> is sometimes used as an abbreviation for "number", in mathematical writing, it's more common to use <code>n</code>. We can also make some modifications by eliminating the <code>break</code>, and by declaring variables closer to where they're used.</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code>std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> <span class="token function">prime_list</span><span class="token punctuation">(</span><span class="token keyword">int</span> limit<span class="token punctuation">)</span>
<span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> primes<span class="token punctuation">{</span><span class="token number">2</span><span class="token punctuation">}</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> n <span class="token operator">=</span> <span class="token number">3</span><span class="token punctuation">;</span> n <span class="token operator"><</span> limit<span class="token punctuation">;</span> n <span class="token operator">+=</span> <span class="token number">2</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
<span class="token keyword">bool</span> isprime <span class="token operator">=</span> <span class="token boolean">true</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> i<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> isprime <span class="token operator">&&</span> primes<span class="token punctuation">[</span>i<span class="token punctuation">]</span> <span class="token operator"><=</span> std<span class="token double-colon punctuation">::</span><span class="token function">sqrt</span><span class="token punctuation">(</span>n<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token operator">++</span>i<span class="token punctuation">)</span> <span class="token punctuation">{</span>
isprime <span class="token operator">&=</span> <span class="token punctuation">(</span>n <span class="token operator">%</span> primes<span class="token punctuation">[</span>i<span class="token punctuation">]</span> <span class="token operator">!=</span> <span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span>isprime<span class="token punctuation">)</span> <span class="token punctuation">{</span>
primes<span class="token punctuation">.</span><span class="token function">push_back</span><span class="token punctuation">(</span>n<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> primes<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>We can also refactor <code>main</code> to use a "range-for" to make it a bit neater:</p> <div class="language-cpp extra-class"><pre class="language-cpp"><code><span class="token keyword">int</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>vector<span class="token operator"><</span><span class="token keyword">int</span><span class="token operator">></span> primes <span class="token operator">=</span> <span class="token function">prime_list</span><span class="token punctuation">(</span><span class="token number">100</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">auto</span> p <span class="token operator">:</span> primes<span class="token punctuation">)</span> <span class="token punctuation">{</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> p <span class="token operator"><<</span> <span class="token string">' '</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
std<span class="token double-colon punctuation">::</span>cout <span class="token operator"><<</span> <span class="token string">'\n'</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>This is just one way refactoring might be done. Others might make different choices. However, the purpose for refactoring remains the same, which is to improve the readability and possibly the performance of the code without necessarily adding features.</p></div> <footer class="page-edit"><div class="edit-link"><a href="https://github.com/devtut/generate/edit/master/docs/cpp/refactoring-techniques.md" target="_blank" rel="noopener noreferrer">Edit this page on GitHub</a> <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></div> <!----></footer> <div class="page-nav"><p class="inner"><span class="prev">
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