#ifndef GRAPH_H
#define GRAPH_H

/* adjacency list implementation */

struct vertex;
struct edge;
struct graph;

struct edge
{
  struct vertex *to;
  struct edge *next;
};

struct vertex
{
  struct edge *adj;
};

struct graph
{
  struct vertex *v;
  unsigned int nv;
};

struct graph *
new_graph (unsigned int nv);

int
new_edge (struct graph *g, unsigned int vi, unsigned int vj);

#endif /* GRAPH_H  */