Adding a vertex to a graph using adjacency list

Question

I'm new in coding, and this is my first attempt on graphs. Basically I have to find the shortest path between two locations using graphs. The arrival time and departure time will be given to us. I am having problem in creating the graph. In the void addloc function I want to add the location to the array of adjacency list everytime I add a new location. How do I do that? Also it would be really helpful if someone could tell me how I can keep the cities as string instead of int. If i keep them as strings I can't use the list as it takes only int or enum as input.

` using namespace std;

class location
{
    public:
        int city;
};

class flightconnect
{
        int arvtime;
        int deptime;
        int arvcity;
    public:
        flightconnect(int _a, int _d, int _c)  { arvtime = _a;  deptime = _d;  arvcity = _c;}
        int getdeptime()        {  return deptime; }
        int getarvtime()        {  return arvtime; }
        int getarvcity()        {  return arvcity; }
};

struct graph
{
    location* vertex;
    list<flightconnect> *adj;
};

void addloc(int a,graph *flight)
{
    flight = new graph;
    flight->vertex->city=a;
    //what should come in the next line?
    flight->adj = flight->adj.append(a);
}

void addflight(int at,int dt,int a,int d,graph *flight)
{
    flightconnect node(at,dt,d);
    flight->adj[a].push_back(node);
}`

asif asif · Accepted Answer · 2013-11-17T07:34:37

In the function void addloc(int a,graph *flight), you are initializing the graph itself.

flight = new graph;

You should initialize the adjacency list for the new city. See here: C++ lists and pointers

You can use map for storing city names in string.

Adding a vertex to a graph using adjacency list

1 Answers