#include <iostream>
#include <map>
#include <utility>

using namespace std;

typedef pair <const int, int> cInt2Int;

int main()
{
   map<int, int> m1;
   map<int, int>::value_type value1;
   map<int, int>::iterator pIter;
   int key1, mapped1;
   
   // value_type can be used to pass the correct type
   // explicitly to avoid implicit type conversion
   m1.insert ( map<int, int>::value_type ( 1, 10 ) );

   // Compare other ways to insert objects into a map
   m1.insert ( make_pair ( 2, 20 ) );
   m1[3] = 30;

   // Initializing key1 and mapped1
   key1 = m1.begin()->first;
   mapped1 = m1.begin()->second;

   cout<<"The key of first element in the map is "<< key1 <<".\n";
   cout<<"The data value of first element in the map is "<< mapped1 <<".\n";

   cout<<"The keys of the mapped elements are:";
   for ( pIter = m1.begin(); pIter != m1.end(); pIter++ )
      cout<<" "<< pIter->first;
   cout<<".\n";

   cout<<"The values of the mapped elements are:";
   for ( pIter = m1.begin(); pIter != m1.end(); pIter++ )
      cout<<" "<< pIter->second;
   cout<<"."<<endl;
}