function arr_encryption(msg) {
  var message = msg.split(' ').join('.'),
      output = '';
      
  // add . if needed
  for (k=0;k<message.length % 6;k++) {
    message += '.';
  }
  
  // [Attack.at.noon] => change
  for (j=0;j<6;j++) {
  	for (i=j;i<message.length;i+=6) {
      output += message[i];
  	}
    if (j<5)output += ' ';
  }
  return output;
}

m = arguments[j=k=0]
  
while(k++<m.length %6) m += O=' '

for (;j<6;O += ' ')
	for (i=j++;d=m[i];i+=6) 
    O += d == ' ' ? '.' : d

return O.trim()