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 ***
本文转自walker snapshot博客51CTO博客，原文链接http://blog.51cto.com/walkerqt/1324824如需转载请自行联系原作者
RQSLT
