STLにセットを実装するC++プログラム

セットは、要素の値が要素を識別するため、各要素が一意である必要がある抽象データ型です。要素の値は、セットに追加されると変更できませんが、その要素の変更された値を削除して追加することはできます。

機能と説明：

Functions used here:
   st.size() = Returns the size of set.
   st.insert() = It is used to insert elements to the set.
   st.erase() = To delete the element from the set.
   st.find() = Returns an iterator to the search element in the set if found, else returns the iterator to
   end. st.begin() = Returns an iterator to the first element in the set.
   st.end() = Returns an iterator to the last element in the set.

サンプルコード

#include <iostream>
#include <set>
#include <string>
#include <cstdlib>
using namespace std;
int main() {
   set<int> st;
   set<int>::iterator it;
   int c, i;
   while (1) {
      cout<<"1.Size of the Set"<<endl;
      cout<<"2.Insert Element into the Set"<<endl;
      cout<<"3.Delete Element of the Set"<<endl;
      cout<<"4.Find Element in a Set"<<endl;
      cout<<"5.Display the set: "<<endl;
      cout<<"6.Exit"<<endl;
      cout<<"Enter your Choice: ";
      cin>>c;
      switch(c) {
         case 1:
            cout<<"Size of the Set: ";
            cout<<st.size()<<endl;
         break;
         case 2:
            cout<<"Enter value to be inserted: ";
            cin>>i;
            st.insert(i);
         break;
         case 3:
            cout<<"Enter the element to be deleted: ";
            cin>>i;
            st.erase(i);
         break;
         case 4:
            cout<<"Enter the element to be found: ";
            cin>>i;
            it = st.find(i);
            if (it != st.end())
               cout<<"Element "<<*it<<" found in the set" <<endl;
            else
               cout<<"No Element Found"<<endl;
         break;
         case 5:
            cout<<"Displaying Set by Iterator: ";
            for (it = st.begin(); it != st.end(); it++) {
               cout << (*it)<<" ";
            }
            cout<<endl;
         break;
         case 6:
            exit(1);
         break;
         default:
            cout<<"Wrong Choice"<<endl;
      }
   }
return 0;
}

出力

1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit

Enter your Choice: 1
Size of the Set: 0
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit


Enter your Choice: 2
Enter value to be inserted: 1
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit

Enter your Choice: 2
Enter value to be inserted: 7
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit

Enter your Choice: 2
Enter value to be inserted: 6
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit

Enter your Choice: 2
Enter value to be inserted: 4
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit

Enter your Choice: 3
Enter the element to be deleted: 1
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit

Enter your Choice: 4
Enter the element to be found: 7
Element 7 found in the set
1.Size of the Set
2.Insert Element into the Set
3.Delete Element of the Set
4.Find Element in a Set
5.Display the set:
6.Exit
Enter your Choice: 6
Exit code: 1