What is better, adjacency lists or adjacency matrices for graph problems in C++?

Question

What is better, adjacency lists or adjacency matrix, for graph problems in C++? What are the advantages and disadvantages of each?

Answer 1

Depending on the Adjacency Matrix implementation the 'n' of the graph should be known earlier for an efficient implementation. If the graph is too dynamic and requires expansion of the matrix every now and then that can also be counted as a downside?