C++类向量反推错误

Question

/usr/include/C++/4.8/ext/new_allocator.h:在实例化'void__gnu_cxx::new_allocator<_tp>::construct(_up*,_args&&...)[with_up=UNDIR_W_EDGE；_args={const UNDIR_W_EDGE&}；_tp=UNDIR_W_EDGE]':/usr/include/c++/4.8/bits/alloc_traits.h:254:4:从'static typename_alloc>::_s_construc(_alloc&,_tp*,_args&&...)[with_tp=UNDIR_W_EDGE；_args={const UNDIR_W_EDGE&}；_alloc=std::allocator；typename std::enable_ifalloc>::_construct_helper<_tp,_args>::value,void>::type=void]“/usr/include/c++/4.8/bits/alloc_traits.h:393:57:”static）...））std::allocator_traits<_alloc>::construc(_alloc&,_tp*,_args&&...)[with_tp=UNDIR_W_EDGE；_args={const UNDIR_W_EDGE&}；_alloc=std::allocator；decltype(_s_construct(__a,__p,（forward<_args>)(std::allocator_traits::construct::__args)...)=]tp=UNDIR_W_EDGE；_alloc=std::allocator；std::vector<_tp,_alloc>::value_type=UNDIR_W_EDGE]“../src/graph.h:31:5:要求从'void graph::addedge（常量Edge&）[with Edge=UNDIR_W_EDGE]”../src/main.cpp:32:13:要求从这里/usr/include/c++/4.8/ext/new_allocator.h:120:4:错误：调用“UNDIR_W_EDGE::UNDIR_W_EDGE (_args)...)；}

#include "vector"

template <typename Edge>
class GRAPH {
 private:
 // Implementation-dependent code
int Vcnt;
int Ecnt;
std::vector<std::vector< Edge > > adj;
 public:
GRAPH(int x):Vcnt(x),Ecnt(0) {

    adj.resize(Vcnt);
}
 virtual ~GRAPH();
 virtual int V() const;
 virtual int E() const;
 virtual void addEdge(const Edge &e){
    adj[e.V()].push_back(e);
    adj[e.W()].push_back(e);
    Ecnt++;
 };
 virtual std::vector< Edge > adjIterator(int) const;
};

 class UNDIR_W_EDGE {
    int v,w;
    float weight;

    public:
     UNDIR_W_EDGE(int v, int w, float weight);
     UNDIR_W_EDGE(UNDIR_W_EDGE &);
     virtual ~UNDIR_W_EDGE();
     virtual int V()const;
     virtual int W()const;
     virtual float WEIGHT()const;
     virtual int CompareTo(UNDIR_W_EDGE e)const;
    };

inline int UNDIR_W_EDGE::CompareTo(UNDIR_W_EDGE e)const{
if(this->weight > e.weight) return 1;
else if (this->weight < e.weight)return -1;
else                            return 0;
}  

GRAPH<UNDIR_W_EDGE> g(10);
UNDIR_W_EDGE e(0,7,0.0);
g.addEdge(e);

Answer 1

您没有undir_w_edge的复制构造函数。

copy构造函数在std::vector 以及compareto中都是必需的，copy构造函数按值取参数（出于某种原因）。

你确实有这个：

UNDIR_W_EDGE(UNDIR_W_EDGE &);

UNDIR_W_EDGE(const UNDIR_W_EDGE&);