map<string, string> how to insert data in this map?

I need to store strings in key value format. So am using Map like below.

#include<map>
using namespace std;
int main()
{
    map<string, string> m;
    string s1 = "1";
    string v1 = "A";

    m.insert(pair<string, str开发者_JAVA技巧ing>(s1, v1)); //Error
}

Am getting below error at insert line

error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'

I tried make_pair function also like below, but that too reports the same error.

m.insert(make_pair(s1, v1));

Pls let me know what's wrong and what's the solution for above problem. After solving above problem, can i use like below to retrieve value based on key

m.find(s1);

I think you miss a #include <string> somewhere.

Could you try this:

#include<string>

It seems the compiler doesn't know how to compare strings. Maybe she doesn't know enough about strings yet, but is too focused on your map to figure that out ATM.

Here is the way to set up map<...,...>

static std::map<std::string, RequestTypes> requestTypesMap = {
   { "order",       RequestTypes::ORDER       },
   { "subscribe",   RequestTypes::SUBSCRIBE   },
   { "unsubscribe", RequestTypes::UNSUBSCRIBE }
};

Try m[s1] = v1; instead.

You have several possibilities how store strings in key value format now:

m["key1"] = "val1";
m.insert(pair<string,string>("key2", "val2"));
m.insert({"key3", "val3"}); // c++11

And traverse it in c++11:

for( auto it = m.begin(); it != m.end(); ++it )
{
  cout << it->first; // key
  string& value = it->second;
  cout << ":" << value << endl;
}

I think it has to do with the fact that <map> doesn't include <string>, but <xstring>. When you are adding elements to the map it needs to find the correct position in the map by sorting. When sorting, map tries to locate the operator <, from which it finds the correct location for the new element. However, there is no operator < for the definition of string in <xstring>, thus you get the error message.

The s1 is an integer you are hoping pass as string...thats likely the main cause of the error!!