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STL中的仿函数？100分送

楼主ailab（）2005-04-19 21:30:53 在 C/C++ / C++ 语言提问

class person{
public:
person(const string& s,int n){name=s;age=n;}
string GetName(){return name;}
int GetAge(){return age;}
private:
string name;
int age;
};

template<class T>
struct great{
bool operator()(const T& x,const T& y){
return (x->GetName()>y->GetName());
}
};
错误提示error C2819: type 'person' does not have an overloaded member 'operator ->'
C:\VC\sort\main.cpp(17) : see declaration of 'person'
C:\VC\sort\main.cpp(29) : while compiling class-template member function 'bool __thiscall great<class person>::operator ()(const class person &,const class person &)'
C:\VC\sort\main.cpp(30) : error C2227: left of '->GetName' must point to class/struct/union
C:\VC\sort\main.cpp(29) : while compiling class-template member function 'bool __thiscall great<class person>::operator ()(const class person &,const class person &)'
C:\VC\sort\main.cpp(30) : error C2819: type 'person' does not have an overloaded member 'operator ->'
C:\VC\sort\main.cpp(17) : see declaration of 'person'
C:\VC\sort\main.cpp(29) : while compiling class-template member function 'bool __thiscall great<class person>::operator ()(const class person &,const class person &)'
C:\VC\sort\main.cpp(30) : error C2227: left of '->GetName' must point to class/struct/union
C:\VC\sort\main.cpp(29) : while compiling class-template member function 'bool __thiscall great<class person>::operator ()(const class person &,const class person &)'
Error executing cl.exe.

不懂，急问，有分问题点数：100、回复次数：12Top

1 楼sunman1982（冥王星）回复于 2005-04-19 21:43:37 得分 0

type 'person' does not have an overloaded member 'operator ->'

完整代码给出来看看Top

2 楼zdy_8212（zdy_8212）回复于 2005-04-19 21:47:05 得分 0

完整的代码!重载部分,STRUCT?有问题.还有就是返回中使用的是指针吗?引用的地方不明析.Top

3 楼bing_huo（我是一个演员！）回复于 2005-04-19 21:53:55 得分 0

return (x->GetName()>y->GetName());

return (x.GetName()>y.GetName()); ????Top

4 楼ailab（）回复于 2005-04-19 21:55:52 得分 0

#include<vector>
#include<string>
#include<algorithm>
#include<iostream>

using namespace std;

/*struct person
{
person(const string& s,int n){name=s;age=n;}
string name;
int age;
};
*/
class person{
public:
person(const string& s,int n){name=s;age=n;}
string GetName(){return name;}
int GetAge(){return age;}
private:
string name;
int age;
};

template<class T>
struct great{
bool operator()(const T& x,const T& y){
return (x->GetName()>y->GetName());
}
};

int main()
{
vector<person> vec;
vec.push_back(person("linxin",20));
vec.push_back(person("wpp",19));
vec.push_back(person("lxwpp",21));
sort(vec.begin(),vec.end(),great<person>());
for(vector<person>::iterator iter=vec.begin();iter!=vec.end();iter++)
cout<<iter->GetName<<" age "<<iter->GetAge<<endl;
return 0;
}Top

5 楼bing_huo（我是一个演员！）回复于 2005-04-19 21:59:51 得分 50

class person{
public:
person(const string& s,int n){name=s;age=n;}
string GetName() const{return name;} //这里
int GetAge() const{return age;} //这里
private:
string name;
int age;
};

template<class T>
struct great{
bool operator()(const T& x,const T& y){
return (x.GetName()>y.GetName());//这里
}
};

int main()
{
vector<person> vec;
vec.push_back(person("linxin",20));
vec.push_back(person("wpp",19));
vec.push_back(person("lxwpp",21));
sort(vec.begin(),vec.end(),great<person>());
for(vector<person>::iterator iter=vec.begin();iter!=vec.end();iter++)
cout<<iter->GetName()<<" age "<<iter->GetAge()<<endl;//这里

system("pause");
return 0;
}

搞定编译运行正确 ~~~~Top

6 楼yangguo_god（狂学java....）回复于 2005-04-19 22:03:18 得分 0

template<class T>
struct great{
bool operator()(const T& x,const T& y){
return (x->GetName()>y->GetName());
}
};

//这里是引用,必须为x.GetName()>y.GetName()Top

7 楼sunman1982（冥王星）回复于 2005-04-19 22:05:38 得分 50

回复人： bing_huo(我是一个演员！) ( ) 信誉：100 2005-04-19 21:59:00 得分: 0

class person{
public:
person(const string& s,int n){name=s;age=n;}
string GetName() const{return name;} //这里
int GetAge() const{return age;} //这里
private:
string name;
int age;
};

template<class T>
struct great{
bool operator()(const T& x,const T& y){
return (x.GetName()>y.GetName());//这里
}
};

int main()
{
vector<person> vec;
vec.push_back(person("linxin",20));
vec.push_back(person("wpp",19));
vec.push_back(person("lxwpp",21));
sort(vec.begin(),vec.end(),great<person>());
for(vector<person>::iterator iter=vec.begin();iter!=vec.end();iter++)
cout<<iter->GetName()<<" age "<<iter->GetAge()<<endl;//这里

system("pause");
return 0;
}

搞定编译运行正确 ~~~~

----------------------------------------------
const的要指向const^_^Top

8 楼ailab（）回复于 2005-04-19 22:09:10 得分 0

OK，结贴，给分Top

9 楼ailab（）回复于 2005-04-19 22:14:24 得分 0

okTop

10 楼ailab（）回复于 2005-04-19 22:15:53 得分 0

怎么给分啊：（Top

11 楼bing_huo（我是一个演员！）回复于 2005-04-19 22:19:12 得分 0

帖子标题后面的管理。。。@_@Top

12 楼owe（wsm）回复于 2005-04-19 22:19:48 得分 0

搞笑！Top