#include <iostream>
#include <map>
     
typedef std::map<std::string,double> Map;
typedef Map::iterator Mapit;
     
int main()
{
    Map m;
    Mapit i;
     
    m["test"]=0.4;
    m["test2"]=-2.4;
     
    for(i = m.begin(); i != m.end(); ++i)
    std::cout << i->first << "=" << i->second << '\n';
     
    m["test2"]=99.9;
     
    for(i = m.begin(); i != m.end(); ++i)
    std::cout << i->first << "=" << i->second << '\n';
     
    m["test2"]+=99.9;
     
    for(i = m.begin(); i != m.end(); ++i)
    std::cout << i->first << "=" << i->second << '\n';

    m["test3"]+=12.34;
     
    for(i = m.begin(); i != m.end(); ++i)
    std::cout << i->first << "=" << i->second << '\n';
}