title: Is it possible for the Keys of a map to be arrays? (Map array error)
body: <p>I want to make a map which has arrays of the form int[27] as Keys, So I tried the following:</p>
  
  <pre><code>#include &lt;map&gt;
  using namespace std;
  map&lt;int[27] ,int&gt; mapa;
  int n[27];
  int main(){
      mapa[n]++;
  }
  </code></pre>
  
  <p>But I get an error, is it because arrays can't be used as key type for a map?<br>
  What can I do in this case? Would it work if I used a vector instead of an array?</p>
  
  <hr>
  
  <p>Is this the suggestion?</p>
  
  <pre><code>#include &lt;cstdio&gt;
  #include &lt;map&gt;
  using namespace std;
  map&lt;array&lt;int,27&gt; ,int&gt; mapa;
  int n[27];
  int main(){
      mapa[n]++;
  }
  </code></pre>
  
  <hr>
  
  <p>This is the version that works:</p>
  
  <pre><code>#include &lt;cstdio&gt;
  #include &lt;map&gt;
  #include &lt;array&gt;
  using namespace std;
  map&lt;array&lt;int,27&gt;, int&gt; mapa;
  array&lt;int,27&gt; v;
  int main(){
      mapa[v]++;
      printf("%d\n",mapa[v]);
  }
  </code></pre>