text: #include <iostream>
  #include <vector>
  #include <set>
  
  using namespace std;
  
  template<class T, class E>
  class Q {
  public:
      T test(T t, E e) {
          return t + e;
      }
  };
  
  int add(int a, int b) {
      return a + b;
  }
  
  float add(float a, float b) {
      return a + b;
  }
  
  template<class T>
  T zz(T a, T b) {
      return a + b;
  }
  
  
  namespace first_space {
      void func() {
          printf("first space func");
      }
  }
  
  namespace second_space {
      void func() {
          printf("second space func");
      }
  }
  
  
  //int main() {
  //
  ////    first_space::func();
  ////    second_space::func();
  ////
  ////    int i = 1;
  ////    int&b = i;
  ////    int c = i;
  ////    printf("\ni is %d,&b is %d,c is %d",&i,&b,&c);
  ////    //i is -274684040,&b is -274684040,c is -274684052
  //
  //    set<int> list;
  //    pair<set<int>::iterator, bool> a = list.insert(1);
  //    cout << a.second << endl;
  //    a = list.insert(1);
  //    cout << a.second << endl;
  //    a = list.insert(2);
  //    cout << a.second << endl;
  //    a = list.insert(2);
  //    cout << a.second << endl;
  //
  //    return 0;
  //}
  