title: Generate random char/digit
body: <p>I`m trying to found fastest way to generate random digit/char array.</p>
  
  <pre><code>char *randomGet(int num) {
      srand(time(NULL));
      const char ab[37] = { "0123456789ABCDEFGHIGKLMNOPQRSTUVWXYZ" };//Alphabet&amp;Digit
      char *targ = new char[num];
      for (int i = 0; i &lt; num; i++) {
          strcat(targ, ab[rand() % 38]);
      }
      return targ;
  }
  </code></pre>
  
  <p>So far I've come up with this, but it does not work (argument of type char is incompatible with parameter of type const char *).
  Help me find the best solution to my problem. Ty.</p>