title: how to find non-alphanumeric in C
body: <p>im trying to separate non-alphanumeric and alphanumeric from a string in C.this is my current code,but if i use this,it will detect all alphanumeric only,while at non-alphanumeric it will return null.so i cant detect at what index are all the non-alphanumeric at.</p>
  
  <pre><code>    char data[] = "http://www.google.com";
      char key[]  = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
      char *find;
  
      find = strpbrk(data,key);
      while(find != NULL){
          printf("%c",*find);
          find = strpbrk(find+1,key);        
      }
  </code></pre>
  
  <p>The output will be httpwwwgooglecom.Thats is what i partially want. i also trying to find where are all the non-alphanumeric at.</p>