I got this question in the exam and i failed to solve it.

[Dodande]

At my exam my first task was:

Write a header for the following main() so it can count the edges of a graph.

  #include <iostream>
  #include <string>
  #include "wgraph.h"

  int main()
  {
  int yourMark = 1;

  WGraph<char, double, true> dirgraph;
  WGraph<std::string, int, false> undirgraph;

  dirgraph.add('A');
  dirgraph.add('B');
  dirgraph.add('C');

  dirgraph.add('A', 'B', 4.54);
  dirgraph.add('C','A', 6.32);

  undirgraph.add("AA", "BB", 3);

  const WGraph<std::string, int, false> c = undirgraph;
  yourMark += (c.is_directed() + dirgraph.is_directed());

  std::cout << "Your mark is " << yourMark << std::endl;

1. I guess I should use template<class T1, class T2 bool directed> class WGraph; which has a vector, but I dont know how to define it.

2. How should this vector store edges since it only contains one vertex?

3. Lastly i faild to understand the function of the bool parameter.



Thank you very much for any advice and help.

[keskiverto]

Why does it look like that you fail on the same question every year?
http://www.cplusplus.com/forum/general/218704/

A graph has vertices and edges. That is not "a vector"; there must be the vertices and the edges somehow.

Directed and undirected graphs have different properties.


Which is more of a problem for you: graphs or C++?
Understanding the problem that the program is made to solve or knowing how to implement a solution with particular language?