c++ - 如何在 vector 中找到某些东西

Question

我有一个指向带有建筑物的 Vector 的指针。

vector<building> * building1;
building1 = gamer.getBuilding(); ( building1 is a pointer to vector with all buildings that gamer has on that moment. )

现在我想检查在那个 vector 中是否存在一个名为 example house 的建筑物..

我以为我可以做类似的事情

vector<building>::iterator it;

it = find((*building1).begin(), (*building1).end(),buildings::house);

其中 buildings 是一个枚举。

但这行不通。

有人可以帮助我吗？

亲切的问候，

Answer 1

答案取决于 building 的定义，您没有显示。但一般来说，当您不想按值查找而是按谓词查找时，您会使用 find_if:

struct building_of_type
{
public:
    explicit building_of_type( buildings type ) : _type( type ){}

    bool operator ()( building const& b ) const {  return is b of type _type?; }
private:
    buildings const _type;
};

std::find_if(
    building1->begin(), building1->end()
  , building_of_type( buildings::house )
);

或者对于更简单的情况:

bool is_building_a_house( building const& b ){ return is b of type house?; }

std::find_if(
    building1->begin(), building1->end()
  , is_building_a_house
);