代码如下:

/*        5. set & multiset    */    set
     
       cities{        "Braunschweig", "Hanover", "Frankfurt", "New York",        "Chicago", "Toronto", "Paris", "Frankfurt"    };    multiset
      
        dup_cities {        "Braunschweig", "Hanover", "Frankfurt", "New York",        "Chicago", "Toronto", "Paris", "Frankfurt"    };    cout << "cities before:" << endl;    ContainerUtil
       
        
         >::printElements(cities);    ContainerUtil
         
          
           >::printElements(dup_cities); cities.insert({ "London", "Munich", "Hanover", "Braunschweig" }); dup_cities.insert({ "London", "Munich", "Hanover", "Braunschweig" }); cout << "cities after:" << endl; ContainerUtil
           
            
             >::printElements(cities); ContainerUtil
             
              
               >::printElements(dup_cities);
              
             
            
           
          
         
        
       
      
     

运行结果:

cities before:

  Braunschweig  Chicago  Frankfurt  Hanover  New York  Paris  Toronto

  Braunschweig  Chicago  Frankfurt  Frankfurt  Hanover  New York  Paris  Toronto

cities after:

  Braunschweig  Chicago  Frankfurt  Hanover  London  Munich  New York  Paris  Toronto

  Braunschweig  Braunschweig  Chicago  Frankfurt  Frankfurt  Hanover  Hanover  London  Munich  New York  Paris  Toronto