Multiset Insert Function in C++ STL

The multiset insert() function in C++ STL which insert elements in the multiset container from a position to another position from one multiset to a different multiset.

List of functions used:

• ms.size() = Returns the size of multiset. 
• ms.insert() = It is used to insert elements to the multiset.

Example Code

#include <iostream>
#include <set>
#include <string>
#include <cstdlib>
using namespace std;
int main() {
   multiset<int> ms;
   multiset<int>::iterator it, it1;
   int c, i;
   while (1) {
      cout<<"1.Size of the Multiset"<<endl;
      cout<<"2.Insert Element into the Multiset"<<endl;
      cout<<"3.Display Multiset"<<endl;
      cout<<"4.Exit"<<endl;
      cout<<"Enter your Choice: ";
      cin>>c;
      switch(c) {
         case 1:
            cout<<"Size of the Multiset: "<<ms.size()<<endl;
         break;
         case 2:
            cout<<"Enter value to be inserted: ";
            cin>>i;
            if (ms.empty())
               it1 = ms.insert(i);
            else
               it1 = ms.insert(it1, i);
         break;
         case 3:
            cout<<"Elements of the Multiset: ";
            for (it = ms.begin(); it != ms.end(); it++)
               cout<<*it<<" ";
            cout<<endl;
         break;
         case 4:
            exit(1);
         break;
         default:
            cout<<"Wrong Choice"<<endl;
      }
   }
return 0;
}

Output

1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 1
Size of the Multiset: 0
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 2
Enter value to be inserted: 1
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 2
Enter value to be inserted: 2
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 2
Enter value to be inserted: 4
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 2
Enter value to be inserted: 6
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 2
Enter value to be inserted: 7
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit

Enter your Choice: 3
Elements of the Multiset: 1 2 4 6 7
1.Size of the Multiset
2.Insert Element into the Multiset
3.Display Multiset
4.Exit
Enter your Choice: 4
exit status 1