排序指针列表 [英] sorting list of pointers
问题描述
使用std :: list;
struct Something {
Something（val）：value（val）{}
bool operator<（Something& s）{返回值< s.value; }
int value;
};
main（）{
list<东西*>东西;
things.pushBack（new Something（10））;
things.pushBack（new Something（20））;
东西。 sort（）;
}
如何强制thing.sort（）使用Something :: operator<（Something&）
而不是默认运算符<指针？
using std::list;
struct Something{
Something( val ): value( val ){}
bool operator<( Something & s ){ return value < s.value; }
int value;
};
main(){
list< Something * > things;
things.pushBack( new Something( 10 ) );
things.pushBack( new Something( 20 ) );
things.sort();
}
How to force things.sort() to use Something::operator<( Something & )
instead of default operator< for pointers ?
推荐答案
Nenad Jalsovec写道：
Nenad Jalsovec wrote:
使用std :: list;
struct Something {
Something（val）：value（val）{}
bool operator<（Something& s）{return value< s.value; }
int value;
};
main（）{
list<东西*>东西;
things.pushBack（new Something（10））;
things.pushBack（new Something（20））;
things.sort（）;
}
如何强制things.sort（）使用Something :: operator<（Something&）
而不是默认运算符<指针？
using std::list;
struct Something{
Something( val ): value( val ){}
bool operator<( Something & s ){ return value < s.value; }
int value;
};
main(){
list< Something * > things;
things.pushBack( new Something( 10 ) );
things.pushBack( new Something( 20 ) );
things.sort();
}
How to force things.sort() to use Something::operator<( Something & )
instead of default operator< for pointers ?
struct Something_ptr_cmp
{
bool operator（Something * lhs，Something * rhs）
{
return * lhs< * rhs;
}
};
// ...
things.sort（Someting_ptr_cmp）;
struct Something_ptr_cmp
{
bool operator(Something* lhs, Something* rhs)
{
return *lhs < *rhs;
}
};
//...
things.sort(Someting_ptr_cmp);
" Rolf Magnus" < RA ****** @ t-online.de>在消息中写道
news：cf ************* @ news.t-online.com ...
"Rolf Magnus" <ra******@t-online.de> wrote in message
news:cf*************@news.t-online.com...
Nenad Jalsovec写道：
Nenad Jalsovec wrote:
使用std :: list;
struct Something {
Something（val）：value（val）{}
bool operator< ;（Something& s）{返回值< s.value; }
int value;
};
main（）{
list<东西*>东西;
things.pushBack（new Something（10））;
things.pushBack（new Something（20））;
things.sort（）;
}
如何强制things.sort（）使用Something :: operator<（Something&）
而不是默认运算符< for pointers？
struct Something_ptr_cmp
{bool operator（Something * lhs，Something * rhs）
using std::list;
struct Something{
Something( val ): value( val ){}
bool operator<( Something & s ){ return value < s.value; }
int value;
};
main(){
list< Something * > things;
things.pushBack( new Something( 10 ) );
things.pushBack( new Something( 20 ) );
things.sort();
}
How to force things.sort() to use Something::operator<( Something & )
instead of default operator< for pointers ?
struct Something_ptr_cmp
{
bool operator(Something* lhs, Something* rhs)
你忘了<了吗？ ;在那里，如：
bool operator<（Something * lhs，Something * rhs）
{
return * lhs< * rhs;
}
};
// ...
things.sort（Someting_ptr_cmp）;
Did you forget the < there, as in:
bool operator <(Something* lhs, Something* rhs)
{
return *lhs < *rhs;
}
};
//...
things.sort(Someting_ptr_cmp);
Howard写道：
Howard wrote:
" Rolf Magnus" < RA ****** @ t-online.de>在消息中写道
新闻：cf ************* @ news.t-online.com ...
"Rolf Magnus" <ra******@t-online.de> wrote in message
news:cf*************@news.t-online.com...
Nenad Jalsovec写道：
Nenad Jalsovec wrote:
>使用std :: list;
>
> struct Something {
> Something（val）：value（val）{}
> bool operator<（Something& s）{返回值< s.value; }
> int值;
> };
>
> main（）{
>列表<东西*>事情;
> things.pushBack（new Something（10））;
> things.pushBack（new Something（20））;
> things.sort（）;
> }
>
>
>
>如何强制things.sort（）使用Something :: operator<（Something&
>）
>而不是默认运算符< for pointers？
> using std::list;
>
> struct Something{
> Something( val ): value( val ){}
> bool operator<( Something & s ){ return value < s.value; }
> int value;
> };
>
> main(){
> list< Something * > things;
> things.pushBack( new Something( 10 ) );
> things.pushBack( new Something( 20 ) );
> things.sort();
> }
>
>
>
> How to force things.sort() to use Something::operator<( Something &
> )
> instead of default operator< for pointers ?
struct Something_ptr_cmp
{bool operator（Something * lhs，Something * rhs）
struct Something_ptr_cmp
{
bool operator(Something* lhs, Something* rhs)
你忘了<在那里，如：
Did you forget the < there, as in:
不，我没有。但是我忘记了额外的事情。应该是：
bool operator（）（某事* lhs，Something * rhs）
想法是有一个比较函数对象可以是
被叫 （这意味着它的operator（）被调用）
算法。
No, I didn''t. But I forgot extra parens. Should be:
bool operator()(Something* lhs, Something* rhs)
The idea is to have a comparison function object that can be
"called" (which means its operator() gets called) by the sort
algorithm.
这篇关于排序指针列表的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
