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更新时间：2022-09-25 19:31:21
按年龄比较Person的大小，直接上代码。
方式一（适用于自定义类型）：
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#include <iostream>#include <string>#include <map>using namespace std;
struct Person
{ Person(string name, int age)
{
this->name = name;
this->age = age;
}
string name;
int age;
bool operator < (const Person &p1) const
{
return this->age < p1.age;
}
};int main()
{ map<Person, string> mm = {
{Person("Alice", 34), "girl"},
{Person("Tom", 23), "boy"},
{Person("Joey", 45), "boy"}
};
for (const auto &p : mm)
{
cout << p.first.name << " * " << p.first.age << " * " << p.second << endl;
}
return 0;
} |
方式二（适用于不可控的类型）：
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#include <iostream>#include <string>#include <map>using namespace std;
struct Person
{ Person(string name, int age)
{
this->name = name;
this->age = age;
}
string name;
int age;
};struct ltPerson
{ bool operator()(const Person &p1, const Person &p2) const
{
return p1.age < p2.age;
}
};int main()
{ map<Person, string, ltPerson> mm = {
{Person("Alice", 34), "girl"},
{Person("Tom", 23), "boy"},
{Person("Joey", 45), "boy"}
};
for (const auto &p : mm)
{
cout << p.first.name << " * " << p.first.age << " * " << p.second << endl;
}
return 0;
} |
运行截图：
*** walker ***
