var is_g = null;
function isPrivateIP(ip) {
   var parts = ip.split('.');
   return parts[0] === '10' || 
      parts[0] === '0' ||
      (parts[0] === '172' && (parseInt(parts[1], 10) >= 16 && parseInt(parts[1], 10) <= 31)) || 
      (parts[0] === '192' && parts[1] === '168');
}

function check_dns(ip) {
//var ip = '5.22.190.198';
var parts = ip.split('.');
var url = 'https://dns.google/resolve?name='+parts[3]+'.'+parts[2]+'.'+parts[1]+'.'+parts[0]+'.in-addr.arpa&type=PTR&cd=true';
 fetch(url)
    .then(function(response) {
      return response.json(); // data into json
    })
    .then(function(data) {
      if(typeof data === 'object'){
          if(typeof data.Answer === 'object' && typeof data.Answer[0] === 'object' && typeof data.Answer[0].data === 'string'){
             if(data.Answer[0].data.includes('cache.google.com')){
                //console.log(data.Answer[0].data);
    			is_g = true;
             }else{
    		 	is_g = false;
    		 }
          }else{
              is_g = false;
          }
      }
    })
    .catch(function(error) {
      console.log(error);
    });
}

getIPs().then(function(res) {
   res.forEach(function(r){
      if(r.includes('.')){
         console.log(r);
         if(!isPrivateIP(r)){
            //console.log(r+' not private');
            check_dns(r);
         }
      }
   });
});