My inner loop xml is not working as expected in C++ vector as expected using write_xml

Question

I have tried to write an xml file using write_xml from vector. But I could not get the desired output as expected.I have given sample input, code, output and the desiredoutput

typedef std::vector<player> playertype;   //vector

static playertype playerList;

typedef struct
{
   std::string Main; //EX: three val after sorting based on name player1,player2,player2
   std::string val1; //EX: three values  100,200,300
   std::string val2;  // EX: three values 250, 200,250
} player;



 if(!playerList.empty())
  {
    ptree tree1,tree2,tree3,tree4;
    playertype::iterator iter;
    std::cout<<"\npsdrec match\n";
    tree1.put("match","2");
    std::string duplicate ="";
    std::sort(playerList.begin(), playerList.end(), sortByMain); //this function will sort out based main value in vector array
    for(iter = playerList.begin(); iter != playerList.end();iter++)
    {
     std::cout<<"First duplicate="<<duplicate<<"\t main_name="<<iter->Main<<"\n";
     if((duplicate.compare(iter->Main)) != 0)
     {   
      std::cout<<"first compare diff val \n";
      tree2.put("main_name",iter->Main);
      tree3.put("name","testmatch");
     }
     tree4.put("tree4",iter->val1);
     tree4.put("runs",iter->val2);
     duplicate = iter->Main;
     ++iter;
     if(iter == playerList.end() || (duplicate.compare(iter->Main)) != 0)  //compare with next value
     {
      std::cout<<"second or last value \n";
      tree3.add_child("value",tree4);
      tree2.add_child("play_matchit",tree3);
      tree1.add_child("playit",tree2);
     }
     --iter;
    std::cout<<"endof loop \n";
    }
    pt.add_child("match_list.match_item",tree1);
  }
  boost::property_tree::xml_writer_settings<char> settings('\t', 1);
  write_xml(filename, pt, std::locale(), settings);

I have got the below output

> <?xml version="1.0" encoding="utf-8"?> <match_list>
>         <match_item>
>                 <match>2</match>
>                 <playit>
>                         <main_name>player1</main_name>
>                         <play_matchit>
>                                 <name>testmatch</name>
>                                 <value>
>                                         <tree4>100</tree4>
>                                         <runs>250</runs>
>                                 </value>
>                         </play_matchit>
>                 </playit>
>                 <playit>
>                         <main_name>player2</main_name>
>                         <play_matchit>
>                                 <name>testmatch</name>
>                                 <value>
>                                         <tree4>100</tree4>
>                                         <runs>250</runs>
>                                 </value>
>                         </play_matchit>
>                         <play_matchit>
>                                 <name>testmatch</name>
>                                 <value>
>                                         <tree4>200</tree4>
>                                         <runs>200</runs>
>                                 </value>
>                                 <value>
>                                         <tree4>300</tree4>
>                                         <runs>250</runs>
>                                 </value>
>                         </play_matchit>
>                 </playit>
>         </match_item> </match_list>

I am getting some executed improper way. Could you please help me to get the desired output?

Expected output:

> <?xml version="1.0" encoding="utf-8"?> <match_list>
>         <match_item>
>                 <match>2</match>
>                 <playit>
>                         <main_name>player1</main_name>
>                         <play_matchit>
>                                 <name>testmatch</name>
>                                 <value>
>                                         <tree4>100</tree4>
>                                         <runs>250</runs>
>                                 </value>
>                         </play_matchit>
>                 </playit>
>                 <playit>
>                         <main_name>player2</main_name>
>                          <play_matchit>
>                                 <name>testmatch</name>
>                                 <value>
>                                         <tree4>200</tree4>
>                                         <runs>200</runs>
>                                         <tree4>300</tree4>
>                                         <runs>250</runs>
>                                 </value>
>                         </play_matchit>
>                 </playit>
>         </match_item> </match_list>

Answer 1

"put" and "put_child" does not allow duplicate entires. "add" and "add_child" allows duplicate entires. In order to get my desired output I changed the code as follows:-

  if(!playerList.empty())
  {
    ptree tree1,tree2,tree3,tree4;
    playertype::iterator iter;
    tree1.put("match","2");
    std::string duplicate ="";
    std::sort(playerList.begin(), playerList.end(), sortByMain); //this function will sort out based main value in vector array
    for(iter = playerList.begin(); iter != playerList.end();)
    {
     std::cout<<"First duplicate="<<duplicate<<"\t main_name="<<iter->Main<<"\n";
     if((duplicate.compare(iter->Main)) != 0)
     {   
      std::cout<<"first compare diff val \n";
      tree2.put("main_name",iter->Main);
      tree3.put("name","testmatch");
     }
      if((duplicate.compare(iter->Main)) == 0)
     { 
     tree4.add("tree4",iter->val1);
     tree4.add("runs",iter->val2);
     }
     else
     {
     tree4.put("tree4",iter->val1);
     tree4.put("runs",iter->val2);
     }
     duplicate = iter->Main;
     ++iter;
     if(iter == playerList.end() || (duplicate.compare(iter->Main)) != 0)  //compare with next value
     {
      std::cout<<"second or last value \n";
      tree3.put_child("value",tree4);
      tree2.put_child("play_matchit",tree3);
      tree1.add_child("playit",tree2);
     }

    std::cout<<"endof loop \n";
    }
    pt.add_child("match_list.match_item",tree1);
  }
  boost::property_tree::xml_writer_settings<char> settings('\t', 1);
  write_xml(filename, pt, std::locale(), settings);