使用char时向量迭代器的问题

Question

我在这里遇到一些问题。我创建了两个向量的矩阵，但是findVertex方法存在问题。

namespace GraphNameSpace
{
  template <class T>
  class Graph
  {
  public:
    Graph<T>();

    void createMatix();
    void insertVertex(T Vertex);
    int findVertex(T Vertex) const;

  private:
    vector<vector<int> > matrix;
    vector<T> objectsVert;

  };
}


template <class T>
void GraphNameSpace::Graph<T>::insertEdge(T fromVertex, T toVertex, int weight=1)
{
  if(dir == UNDIRECTED)
  {
    matrix[findVertex(toVertex)][findVertex(fromVertex)] = weight;
    matrix[findVertex(fromVertex)][findVertex(toVertex)] = weight;
  }
  else
    matrix[findVertex(fromVertex)][findVertex(toVertex)] = weight;



template <class T>
int GraphNameSpace::Graph<T>::findVertex(T Vertex) const
{
  for(typename vector<T>::iterator it = objectsVert.begin(); it < objectsVert.end(); it++)
  {
      if(*it == Vertex)
      {
          return it - objectsVert.begin(); 
      }
  }
  return 0;
}

***********************在主要********************** ***

int main()
{
   Graph<char> Graph3(DIRECTED,WEIGHTED);

   char A = 'A';
   Graph3.insertVertex(A);
   Graph3.insertEdge(A,B,5);
}

问题似乎源于每当使用char时，因为它给了我这个错误：

从'std :: vector＆gt; :: const_iterator转换{aka __gnu_cxx :: __ normal_iterator＆gt; ＆gt;}'到非标量类型'std :: vector＆gt; :: iterator {aka __gnu_cxx :: __ normal_iterator＆gt; ＆gt;}'要求