set-upper_bound

////////////////////////////////////////
//      2018/04/29 15:33:59
//      set-upper_bound

// returns an iterator to the first element greater than a certain value

#include <iostream>
#include <set>
#include <iomanip>
#include <string>

using namespace std;

template<class T>
class Member{
private:
    T first, last;
public:

    Member(T l) :last(l), first(""){}

    Member(T l, T f) : last(l), first(f){}

    void print() const{
        cout.setf(ios::left);
        cout << setw(15) << first << " " << last << endl;
    }

    friend  bool operator <(const Member& m1, const Member& m2){
        return m1.last < m2.last;
    }

    friend bool operator == (const Member& m1, const Member& m2){
        return m1.last == m2.last;
    }
};

//=================================
int main(){
    typedef Member<string> M;
    typedef set<M, less<M>> S;
    S s;

    s.insert(M("Smith","John"));
    s.insert(M("Shevchenko","Taras"));
    s.insert(M("Amstrong","Bill"));
    s.insert(M("Bain","Linda"));
    s.insert(M("Pushkin","Alexander"));
    s.insert(M("Pasternak","Boris"));

    S::iterator it = s.begin();
    while (it != s.end())
    {
        (it++)->print();
    }
    cout << endl;

    M m1("P");
    M m2("Pzz");
    S::iterator low = s.lower_bound(m1);
    S::iterator upp = s.upper_bound(m2);

    it = low;
    while (it != upp)
    {
        (it++)->print();
    }
    cout << endl;

    return 0;
}


/*
OUTPUT:
    Bill            Amstrong
    Linda           Bain
    Boris           Pasternak
    Alexander       Pushkin
    Taras           Shevchenko
    John            Smith

    Boris           Pasternak
    Alexander       Pushkin
*/ 
原文地址:https://www.cnblogs.com/laohaozi/p/12537887.html