/in/foo.cc: In function 'int main()':
/in/foo.cc:6:2: error: 'cin' was not declared in this scope
  cin>>C>>R;
  ^~~
/in/foo.cc:6:2: note: suggested alternative:
In file included from /in/foo.cc:1:0:
/usr/include/c++/7/iostream:60:18: note:   'std::cin'
   extern istream cin;  /// Linked to standard input
                  ^~~
/in/foo.cc:9:2: error: 'MGraph' was not declared in this scope
  MGraph M;
  ^~~~~~
/in/foo.cc:9:2: note: suggested alternative: 'isgraph'
  MGraph M;
  ^~~~~~
  isgraph
/in/foo.cc:10:2: error: 'M' was not declared in this scope
  M.DFSTraverse();
  ^
/in/foo.cc: At global scope:
/in/foo.cc:32:11: error: expected ')' before 'v'
  MGraph(T v[],int n,int e);
           ^
/in/foo.cc: In member function 'void MGraph::DFS(int, bool*)':
/in/foo.cc:21:3: error: 'cout' was not declared in this scope
   cout<<vexs[v];
   ^~~~
/in/foo.cc:21:3: note: suggested alternative:
In file included from /in/foo.cc:1:0:
/usr/include/c++/7/iostream:61:18: note:   'std::cout'
   extern ostream cout;  /// Linked to standard output
                  ^~~~
/in/foo.cc:21:9: error: 'vexs' was not declared in this scope
   cout<<vexs[v];
         ^~~~
/in/foo.cc:21:9: note: suggested alternative: 'gets'
   cout<<vexs[v];
         ^~~~
         gets
/in/foo.cc:25:7: error: 'edge' was not declared in this scope
    if(edge[v][i]==1&&!visited[i])
       ^~~~
/in/foo.cc:25:7: note: suggested alternative: 'edgenum'
    if(edge[v][i]==1&&!visited[i])
       ^~~~
       edgenum