在STL中实现集的C ++程序
Set是抽象数据类型，其中每个元素都必须是唯一的，因为元素的值可以标识它。一旦将元素的值添加到集合中，就无法对其进行修改，但是可以删除并添加该元素的修改后的值。
功能和说明：
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.
范例程式码
#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;
}输出结果
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