C++ code is printing the both the correct answer plus extra ones to my output file

My program is supposed to gather input from a .txt and run it through the code and output the information into a output.txt, but when it does read it, it outputs extra information for some reason and I am not sure why it is doing that.

Code:

#include<iostream>
#include<string>
#include<set>
#include<fstream>
#include "ArgumentManager.h"

using namespace std;
class Book{
    public:
    string genre,title,author,year;
    Book(string given_genre, string given_title,string given_author,string given_year)
    {
      genre = given_genre;
      title = given_title;
      author = given_author;
      year = given_year;
    }
};

Book* processData(string dataRow)
{
  string genre,title,author,year;
  genre = title = author = year = "NULL";
  string key = "", value = "";
  int i=0;
  bool isKey = true;
  while(dataRow[i] != '}')
  {
    if(dataRow[i] == ' ' || dataRow[i] == '{')
    {
      i++;
      continue;
      }
    if(dataRow[i] == ',')
    {
      if(key == "genre")
      {
        genre = value;
        }
        if(key == "title")
        {
          title = value;
          }
          if(key == "author")
          {
            if(title == "NULL")
            {
              return NULL;
              }
            author = value;
            }
            if(key == "year")
            {
              if(author == "NULL")
              {
                return NULL;
              }
            year = value;
            }
            key = "";
            value = "";
            isKey = true;
    }
    else if(dataRow[i] == ':')
    {
      isKey = false;
      }
    else{
      if(isKey)
        key+=dataRow[i];
      else
          value+=dataRow[i];
      }
      i++;
    }
    if(key == "year")
    {
      if(author == "NULL")
        return NULL;
      year = value;
    }
    if(key == "genre")
    {
      genre = value;
    }
    Book *book = new Book(genre,title,author,year);
    return book;
}

pair<string,string> processCommand(string command)
{
  bool isKey = true;
  string key="",value="";
  for(int i=0;i<command.length();i++)
  {
    if(command[i] == ' ')
      continue;
    if(command[i] == ':')
    {
      isKey = false;
      continue;
      }
    if(isKey)
    {
      key+=command[i];
      }
    else
    {
      value+=command[i];
      }
  }
  return make_pair(key,value);
}

int main(int argc, char* argv[])
{
  ArgumentManager am(argc, argv);
  ifstream input;
  ofstream output;

  string infileName = am.get("input");
  string outfileName = am.get("output");
  string cmdfilename = am.get("command");
  input.open(infileName);
  output.open(outfileName);


  string dataRow;
  int booksSize = 0;
  Book* books[10000];
  while(getline(input,dataRow))
  {
    Book* book = processData(dataRow);
    if(book != NULL)
    {
      books[booksSize++] = book;
    }
  }
  ifstream commands("command.txt");
  string commandRow;
  set<string> genre_bucket,title_bucket,author_bucket,year_bucket;
    
  while(getline(commands,commandRow))
  {
    pair<string,string> command = processCommand(commandRow);
    if(command.first == "genre")
      genre_bucket.insert(command.second);
    if(command.first == "title")
      title_bucket.insert(command.second);
    if(command.first == "author")
      author_bucket.insert(command.second);
    if(command.first == "year")
      year_bucket.insert(command.second);
  }
  Book* selectedBooks[10000];
  int selectBooksSize = 0;
  for(int i=0; i < booksSize ;i++)
  {
    if(books[i]->genre !="NULL" && genre_bucket.count(books[i]->genre) == 0 && genre_bucket.size() > 0)
      continue;
    if(title_bucket.size() > 0 && title_bucket.count(books[i]->title) == 0)
      continue;
    if(author_bucket.size() > 0 && author_bucket.count(books[i]->author) == 0)
      continue;
    if(year_bucket.size() > 0 && year_bucket.count(books[i]->year) == 0)
      continue;
    selectedBooks[selectBooksSize++] = books[i];
  }

  for(int i=0; i < selectBooksSize ;i++)
  {
    if(selectedBooks[i]->genre != "NULL")
      output<<"{genre:"<<selectedBooks[i]->genre<<","<<"title:"<<selectedBooks[i]->title<<","<<"author:"<<selectedBooks[i]->author<<","<<"year:"<<selectedBooks[i]->year<<"}"<<endl;
    else
      output<<"{title:"<<selectedBooks[i]->title<<","<<"author:"<<selectedBooks[i]->author<<","<<"year:"<<selectedBooks[i]->year<<"}"<<endl;
  }
  return 0;
}

the input is:

{genre:fiction,title:Oliver.Twist,author:Cha rles.Dickens,year:18 38}
{genre:child.literature,title:the.cat.in.the.  hat,author:Dr.Seus s,year:1957}
{genre:child.lit e  rature,ti  tle:Green.Eggs.And.H  am, author:Dr.Seu ss,year:1960}

{genre:ficti on,title:Great.Expec tations,autho r:Char les.Dickens,year:1861}
{genre:f ict i on, title:A.Chrismas.Carol,author:Charles.D icke ns,year:1843}
{genre:fict ion ,title : The.House.Of.The.Dead,a uthor:Fyod or.Dostoevsky,year:1861}
{genre:fiction,titl e:The.Old.Man.And.The.Sea,author:Ernest.Hemingway,year:1957}




{g e n re: f ic tion , title:Gr eat.Exp ectation s,auth or:Charles.Dickens,year:1861}
{genre:chi ld.literat u r e, ti tl e:G reen.Eggs.A nd.Ha m, auth  or:Dr.Seuss,year:1960}

and the output SHOULD be this:

{genre:fiction,title:Great.Expectations,author:Charles.Dickens,year:1861}
{genre:fiction,title:The.House.Of.The.Dead,author:Fyodor.Dostoevsky,year:1861}
{genre:fiction,title:The.Old.Man.And.The.Sea,author:Ernest.Hemingway,year:1957}
{genre:fiction,title:Great.Expectations,author:Charles.Dickens,year:1861}

but instead it keep giving me this output:

{genre:fiction,title:Oliver.Twist,author:Charles.Dickens,year:1838}
{genre:child.literature,title:the.cat.in.the.hat,author:Dr.Seuss,year:1957}
{genre:child.literature,title:Green.Eggs.And.Ham,author:Dr.Seuss,year:1960}
{title:NULL,author:NULL,year:NULL}
{genre:fiction,title:Great.Expectations,author:Charles.Dickens,year:1861}
{genre:fiction,title:A.Chrismas.Carol,author:Charles.Dickens,year:1843}
{genre:fiction,title:The.House.Of.The.Dead,author:Fyodor.Dostoevsky,year:1861}
{genre:fiction,title:The.Old.Man.And.The.Sea,author:Ernest.Hemingway,year:1957}
{title:NULL,author:NULL,year:NULL}
{title:NULL,author:NULL,year:NULL}
{title:NULL,author:NULL,year:NULL}
{title:NULL,author:NULL,year:NULL}
{genre:fiction,title:Great.Expectations,author:Charles.Dickens,year:1861}
{genre:child.literature,title:Green.Eggs.And.Ham,author:Dr.Seuss,year:1960}