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@@ -42,3 +42,7 @@ The function will be called recursively and will be stored in call stack for all
   <span class="token cBase">[</span>arr<span class="token cBase">[</span>left<span class="token cBase">]</span><span class="token cBase">,</span> arr<span class="token cBase">[</span>right<span class="token cBase">]</span><span class="token cBase">]</span> <span class="token cBase">=</span> <span class="token cBase">[</span>arr<span class="token cBase">[</span>right<span class="token cBase">]</span><span class="token cBase">,</span> arr<span class="token cBase">[</span>left<span class="token cBase">]</span><span class="token cBase">]</span><span class="token cBase">;</span>
   <span class="token cVar">return</span> arr<span class="token cBase">.</span><span class="token cMod">join</span><span class="token cBase">(</span><span class="token cString">''</span><span class="token cBase">)</span><span class="token cBase">;</span>
 <span class="token cBase">}</span></code></pre></div></div></div><div class="row my-2"><div><span><i>Source:</i>&nbsp;<span><a href="https://stackoverflow.com/questions/4240080/generating-all-permutations-of-a-given-string/4240098#4240098" rel="noreferrer" target="_blank" title="Find all the Permutations of a String Interview Questions Source To Answer">stackoverflow.com</a></span></span>&nbsp; &nbsp;</div></div></div></div></div> <br data-v-4865b274=""><br data-v-4865b274=""></div><div data-v-4865b274="" data-v-43a77f0d=""><div data-v-4865b274=""><h2 data-v-4865b274="">🔹 8. Explain what is Explicit and Implicit Backtracking Constrains?</h2></div> <div data-v-4865b274=""><h3 data-v-4865b274="">Answer:</h3> <div data-v-4865b274=""><div><div><div class="AnswerBody"><ul><li><strong>Explicit constraints</strong> are rules that restrict each <em>elements</em> (nodes) of <em>solution space</em> only from a given, predefined set (described by some <em>Explicit rules</em>)</li><li><strong>Implicit constraints</strong> describe the way in which the <em>elements</em> (nodes) of <em>solution space</em> must relate (depend) to <em>each other</em>.</li></ul></div></div><div class="row my-2"><div><span><i>Source:</i>&nbsp;<span><a href="http://www.cs.umsl.edu/~sanjiv/classes/cs5130/lectures/bt.pdf" rel="noreferrer" target="_blank" title="Explain what is Explicit and Implicit Backtracking Constrains? Interview Questions Source To Answer">www.cs.umsl.edu</a></span></span>&nbsp; &nbsp;</div></div></div></div></div> <br data-v-4865b274=""><br data-v-4865b274=""></div></div>
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+> You can also find more data structures interview questions here 👉🏼 https://devinterview.io/data/backtracking-interview-questions