C++ set示例

set是一种集合，其中包含0个或多个不重复、不排序的元素（key）

multiset允许有重复key的set

常用函数：insert，find

//set#include<iostream>#include<set>using namespace std;int main(){typedef set<int,greater<int> >    IntSet;IntSet s1;s1.insert(4);s1.insert(3);s1.insert(5);s1.insert(1);s1.insert(6);s1.insert(2);s1.insert(5);//the inserted element that has the same value existedcopy(s1.begin(), s1.end(), ostream_iterator<int>(cout, " "));cout<<endl<<endl;pair<IntSet::iterator, bool> status=s1.insert(4);if(status.second)cout<<"4 is inserted as element"    <<distance(s1.begin(), status.first)+1<<endl;elsecout<<"4 is already exists in s1"<<endl;copy(s1.begin(), s1.end(), ostream_iterator<int>(cout, " "));cout<<endl<<endl;return 0;}