tokens: When you type 4 bytes , this is turned into a 32-bit int value e.g . 5 , \n , \n , \n is about 900 million which is why it complains about memory when you create the array .
ner_tags: O O O O O O O O O O O O B-Data_Type O O O B-Value O B-Value O B-Value O B-Value O O O O O O O O O O O O O O O B-Data_Structure O