Question

i have a std::map and i am using iterator to find a certain key,value pair. After finding it i am unable to get the position of the key,value pair from the iterator. By doing another find i can get it, but i want a work around for this.

//mycode is this

std::map<std::string,myclass*> mymap;

size_t myfind(const std::string &s)
{

std::map<std:string,myclass*>::iterator i=mymap.find(s);

if((i==mymap.end())||((*i).second==0))
{
std::cout<<"some error\n";
}

else
{
//here i need to return the size_t value of the iterator i
}

}

NOTE: edited size_t as the position of key,value pair

Answer 1

If you want to return the “position” of the result:

#include <iterator>
// ...

std::map<std::string,myclass*> mymap;

size_t myfind(const std::string &s)
{

    std::map<std:string,myclass*>::iterator i=mymap.find(s);

    if((i==mymap.end())||((*i).second==0))
    {
        std::cout<<"some error\n";
    }

    else
    {
        return std::distance(mymap.begin(), i);
    }
}

However, you are probably better off just returning the iterator!