typedef struct {
   const char* city_name;
} GraphNode;

typedef struct {
    unsigned int node_a;
    unsigned int node_b;
}  GraphEdge;

#define MAX_GRAPH_NODE_COUNT 1024
#define MAX_GRAPH_EDGE_COUNT 2048


int main(void) {
  GraphNode nodes[MAX_GRAPH_NODE_COUNT]; // Node array
  GraphEdge edges[MAX_GRAPH_EDGE_COUNT]; // Edge array

  int node_count = 2;
  int edge_count = 1:

  GraphNode node_a = {"London"};
  GraphNode node_b = {"Birmingham"};

  memcpy(&nodes[0], node_a, sizeof(node_a)); // Put node at index 0, so id = 0 for Node A aka London
  memcpy(&nodes[1], node_a, sizeof(node_b)); // Put node at index 1, so id = 1 for Node B aka Birmingham

  edges[0] = {0, 1}; // Edge 0 connects London and Birmingham aka Node A and B aka node[0] and node[1].

  return 0;
}