#include <iostream>
#include <map>
#include <string>
using namespace std;
int main()
{ map <string, int> m = {{"z", 2},{"y", 1},{"x", 3}};
  map <string, int> :: iterator i;
  m["a"]=4;
  cout <<m["y"]<<endl;                         // 1
  for (i= m.begin(); i != m.end(); i++)
  cout <<"{"<<i->first<< ","<< i->second<<"} ";// {a,4} {x,3} {y,1} {z,2} 
  return 0;
}