CS 1501
Graph code segments from Sedgewick text
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CHAPTER 30 Connectivity   
 
int visit(int k) // DFS to find articulation points
  {
    struct node *t; 
    int m, min;
    val[k] = ++id; 
    min = id;
    for (t = adj[k]; t != z; t = t->next)
      if (val[t->v] == unseen) 
        {
          m = visit(t->v);
          if (m < min) min = m;
          if (m >= val[k]) cout << name(k);
        }
      else if (val[t->v] < min) min = val[t->v];
    return min;
  }

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CHAPTER 31 Weighted Graphs  
 
PQ pq(maxV);
visit(int k) // PFS, adjacency lists
  {
    struct node *t;
    if (pq.update(k, -unseen) != 0) dad[k] = 0;
    while (!pq.empty())
      {
        id++; k = pq.remove(); val[k] = -val[k];
        if (val[k] == -unseen) val[k] = 0;
        for (t = adj[k]; t != z; t = t->next)
          if (val[t->v] < 0) 
            if (pq.update(t->v, priority))
              { 
                val[t->v] = -(priority); 
                dad[t->v] = k; 
              }
      }
  }
 
void kruskal()
 {
  int i, m, V, E;
  struct edge
    { char v1, v2; int w; };
  struct edge e[maxE];
  PQ pq(maxE); EQ eq(maxE);
  cin >> V >> E;
  for (i = 1; i <= E; i++)
      cin >> e[i].v1 >> e[i].v2 >> e[i].w;
  for (i = 1; i <= E; i++)
      pq.insert(i, e[i].w);
  for (i = 0; i < V-1; )
    {
      if (pq.empty()) break; else m = pq.remove(); 
      if (eq.find(index(e[m].v1),index(e[m].v2),1))
        { cout << e[m].v1 << e[m].v2 << ' '; i++; };
    }
 }
 
void search() // PFS, adjacency matrix
  {
    int k, t, min = 0;
    for (k = 1; k <= V; k++) 
      { val[k] = unseen; dad[k] = 0; }
    val[0] = unseen-1;
    for (k = 1; k != 0; k = min, min = 0)
      {
        val[k] = -val[k];
        if (val[k] == -unseen) val[k] = 0;
        for (t = 1; t <= V; t++)
          if (val[t] < 0)
            {
              if (a[k][t] && (val[t] < -priority))
                { val[t] = -priority; dad[t] = k; }
              if (val[t] > val[min]) min = t;
            }
        }
  }