24_unordered_set2.cpp

#include <iostream>
#include <unordered_set>
#include "show.h"

struct People
{
    std::string name;
    int age;

    People(std::string n, int a) : name(n), age(a) {}
};

struct PeopleHash
{
    inline std::size_t operator()(const People &p) const
    {
        std::hash<int> hi;
        std::hash<std::string> hs;
        return hs(p.name) + hi(p.age);
    }
};

struct PeopleEqual
{
    inline bool operator()(const People &p1, const People &p2) const
    {
        return (p1.name == p2.name) && (p1.age == p2.age);
    }
};

// 사용자 정의타입에 대한 hash
int main()
{
    std::unordered_set<People, PeopleHash, PeopleEqual> s;

    s.emplace("kim", 20); // s.insert( People("kim",20))
    s.emplace("lee", 25);
    s.emplace("park", 30);

    People peo("lee", 25);
    auto p = s.find(peo);

    std::cout << (*p).name << std::endl;
}