set

 1        set<int>s1;
 2     multiset<int>s2;
 3     int  x;
 4     for(int i=1;i<=3;i++)
 5     {
 6         scanf("%d",&x);
 7         s1.insert(x);
 8         s2.insert(x);
 9     }
10     for(auto it=s1.begin();it!=s1.end();it++){
11         cout<<*it<<endl;
12     }
13     cout<<"frvbfeb
";
14     for(auto it=s2.begin();it!=s2.end();it++){
15         cout<<*it<<endl;
16     }
17     
18     /*
19     
20     
21     5 1 1
22 1
23 5
24 frvbfeb
25 1
26 1
27 5
28 
29 */

insert
erase
clear
count

 1 //遍历
 2 set<int>s;
 3 int  main()
 4 {
 5    for(int  i=1;i<=3;i++) s.insert(i);
 6    for(auto x :s) printf("%d
",x);
 7 }
 8 1
 9 2
10 3

 1 char c;
 2 int n,y;
 3 set<int>se;
 4 set<int>::iterator it1,it2,it3;
 5 int  main()
 6 {  
 7   for(int i=1;i<=5;i++){
 8       se.insert(i);
 9   }
10  
11   it1 = se.begin();
12   it2 = se.begin();
13   it2++;it2++;
14   se.erase(it1,it2);[)
15   printf("%d
",*it2);
16 
17   for(it3=se.begin();it3!=se.end();it3++) printf("%d
",*it3);
18     return 0;
19 }