#include <string> 
#include <map> 
#include <iostream> 

using namespace std; 

struct arrtibute 
{ 
       const char* name; 
       int id; 
}; 

typedef std::map <std::string, arrtibute*> AtrributMap; 
AtrributMap atrributeMap_g; 
const int MaxCount = 3;

void InitData() 
{ 
       for (int i = 0; i  < MaxCount; i++) 
       { 

               static arrtibute atrr; 
               std::string str; 

               cout  < <"Input the name: "; 
               cin>>str; 

               atrr.id = i; 
               atrr.name = str.c_str(); 

               std::pair <AtrributMap::iterator,bool> insResult; 
               insResult = atrributeMap_g.insert(std::make_pair(atrr.name, &atrr)); 

               // Make sure added successfully 
               if (!insResult.second) 
               { 
                      cout < <"insert to transfer map failed, id and name is: "  
                              < <atrr.id < <"  " < <atrr.name < <endl; 
               } 
       } 
} 

void PrintData() 
{ 
       cout < <"**********print the map*********" < <endl; 
       AtrributMap::const_iterator Itor; 
       for( Itor = atrributeMap_g.begin(); 
       Itor != atrributeMap_g.end(); 
       ++Itor ) 
       { 
              cout < <"name is: " < <Itor->second->name < <" " < <"Id is : " < <
                    Itor->second->id < <endl; 
       } 
       cout < <"**********end of the map*********" < <endl; 
} 

The above code have a problem: I insert 3 iterm into the global map atrributeMap_g, when I output the map there is an error:
all the 3 item have different value but the same id which is the last time insert id. I think this may caused by the key:atrr.name.
Since atrr.name is const char* which compare with the address in map key compare implementation, but I want to compare the string.
So I try to do std::string strName(atrr.name) to convert const char* to std::string then atrributeMap_g.insert(std::make_pair(strName, &atrr)),
but this take no effect.
How to loop to insert correctly under the conditon that do not change the definition of struct arrtibute and map AtrributMap.

Thanks a lot!

Edited 3 Years Ago by Dani: Formatting fixed

it doesn't print any errors for me

one of the problems that you have of course is that you only have one "arrtibute" object in the entire program; so the values of the map all point to the same object

It can print but not the item I want.
Do you know how to insert the item correctly I input.
ps: Do not change the definition of struct arrtibute .
Thanks.

here atrr is declared as static as i result that the address that you are inserting into the vector is same everytime.

insResult = atrributeMap_g.insert(std::make_pair(atrr.name, &atrr));

as a result when you do

Itor->second->name;
Itor->second->id ;

you get the same values everytime.
can you print the address and confirm this?

well I can see several errors.
I don't know your level of C++, but assume you must be good enough, because you are using STL.

struct attribute { 
	const char* name;
	int id;
};


int main () 
{
	static attribute attr;
	std::string str = "Laiq";
	
	attribute* attrPtr = 0;			//points to nothing...

	attr.name	 = str.c_str ();
	attr.id		 = 4;

	attrPtr = &attr;			// I point to attr here....

	cout<< attr.name<<endl;
	cout<< attr.id <<endl;
	cout<<"The address of Pointer 1 is :"<<attrPtr<<endl;

	str = "Ahmed";

	attribute* attrPtr2 = 0;
	attr.name = str.c_str ();
	attr.id = 18;

	
	attrPtr2 = &attr;

	cout<< attr.name<<endl;
	cout<< attr.id<<endl;
	cout<< "The address of Pointer 2 is : "<<attrPtr2<<endl;

	// Intersting.
	cout<<"The contents of both pointer are same....."<<endl;
	cout<<"The name of Ptr1 is \""<<attrPtr->name<< "\" and the name of Ptr2 is \""<<attrPtr2->name<<"\""<<endl;
	cout<<"The id of Ptr1 is \""<<attrPtr->id<< "\" and the id of Ptr2 is \""<<attrPtr2->id<<"\""<<endl;

	return 0;
}

The above code explains a lot.. try to comprehend what you are actually doing.

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