static void sweep(ArrayList<Integer> indexes) {
    PriorityQueue<Event> pq = new PriorityQueue<Event>();
    for (int i = 0; i < indexes.size(); i++) {
      pq.offer(new Event(lo[val[indexes.get(i)]] + 1, 1, indexes.get(i)));
      pq.offer(new Event(hi[val[indexes.get(i)]], -1, indexes.get(i)));
    }

    TreeSet<Integer> active = new TreeSet<Integer>();
    while (!pq.isEmpty()) {
      Event curr = pq.poll();
      if (curr.type == 1) active.add(curr.index);
      else if (curr.type == -1) {
        active.remove(curr.index);
        Integer lower = active.lower(curr.index);
        if (lower != null && lower > lo[val[curr.index]]) {
          Interval add = new Interval(lower, curr.index);
          Interval prev = intervals.floor(add);
          Interval next = intervals.ceiling(add);
          boolean intersectPrev = true;
          boolean intersectNext = true;

          if (prev != null) {
            if (Math.max(add.l, prev.l) < Math.min(add.r, prev.r)) {
              if (add.r - add.l <= prev.r - prev.l) {
                intervals.remove(prev);
                intersectPrev = false;
              }
            } else {
              intersectPrev = false;
            }
          } else {
            intersectPrev = false;
          }

          if (next != null) {
            if (Math.max(add.l, next.l) < Math.min(add.r, next.r)) {
              if (add.r - add.l <= next.r - next.l) {
                intervals.remove(next);
                intersectNext = false;
              }
            } else {
              intersectNext = false;
            }
          } else {
            intersectNext = false;
          }

          if (!intersectPrev && !intersectNext) intervals.add(add);
        }
      }
    }
  }
Exemplo n.º 2
0
  static void solve(Scanner sc) throws IOException {
    int h = sc.nextInt();
    int w = sc.nextInt();
    int k = sc.nextInt();
    PriorityQueue<Node> pq = new PriorityQueue<Node>();
    for (int i = 0; i < h; i++) {
      String s = sc.next();
      for (int j = 0; j < w; j++) {
        grid[i][j] = s.charAt(j);
        dis[i][j] = grid[i][j] == '#' ? 0 : inf;
        if (grid[i][j] == 'S') pq.offer(new Node(i, j, 0));
      }
    }

    // Dijkstra
    // There is always a solution according to problem statement
    while (!pq.isEmpty()) {
      Node z = pq.poll();
      int x = z.x;
      int y = z.y;
      int d = z.dis;
      if (d > dis[x][y]) continue;
      if (x == 0 || x == h - 1 || y == 0 || y == w - 1) {
        System.out.println(d + 1);
        break;
      }
      for (int i = 0; i < 4; i++) {
        int nx = x + dx[i];
        int ny = y + dy[i];
        // if(nx<0||nx>=h||ny<0||ny>=w)
        //    continue;
        int nd = d + 1 + (grid[nx][ny] == '@' ? k : 0);
        if (nd < dis[nx][ny]) {
          dis[nx][ny] = nd;
          pq.offer(new Node(nx, ny, nd));
        }
      }
    }
  }
 // 保存待访问的URL及其优先级
 private static void SavePriorQueue(String filepath) throws Exception {
   BufferedWriter bw = new BufferedWriter(new FileWriter(filepath));
   PriorityQueue<UrlValue> temp = new PriorityQueue<UrlValue>();
   UrlValue cur = null;
   while (pq.peek() != null) {
     cur = pq.remove();
     temp.offer(cur);
     bw.write(cur.url + " " + cur.value);
     bw.newLine();
   }
   pq = temp;
   bw.flush();
   bw.close();
 }
 // 清除所有优先队列的数据,设置优先种子
 private static void SetSeeds(String filepath) throws Exception {
   pq.clear();
   BufferedReader br = new BufferedReader(new FileReader(filepath));
   String line = null;
   UrlValue cur = null;
   visitedPrint();
   while ((line = br.readLine()) != null) {
     line = line.trim();
     // System.out.println(line);
     if (!line.equals("")) {
       if (!visitedUrl.contains(line)) {
         cur = new UrlValue();
         cur.url = line;
         cur.value = 1;
         pq.offer(cur);
       } else {
         System.out.println("contain");
       }
     }
   }
   br.close();
 }
  // 加载待访问的url
  private static void SetPriorQueue(String filePath) throws Exception {
    BufferedReader br = new BufferedReader(new FileReader(filePath));
    Scanner sc = null;
    String line = null;
    String url = null;
    UrlValue cur = null;

    while ((line = br.readLine()) != null) {
      line = line.trim();
      if (!line.equals("")) {
        sc = new Scanner(line);
        url = sc.next();
        if (!visitedUrl.contains(url)) {
          cur = new UrlValue();
          cur.url = url;
          cur.value = sc.nextDouble();
          pq.offer(cur);
        }
      }
    }
    br.close();
  }
Exemplo n.º 6
0
 public static void main(String[] args) throws Exception {
   BufferedReader br = new BufferedReader(new FileReader(new File(args[0])));
   BufferedWriter bw = new BufferedWriter(new FileWriter(args[1]));
   int T = Integer.parseInt(br.readLine());
   for (int t = 1; t <= T; t++) {
     br.readLine();
     List<List<Station>> graph = new ArrayList<>();
     int N = Integer.parseInt(br.readLine());
     for (int i = 0; i < N; i++) {
       graph.add(new ArrayList<>());
       String[] line1 = br.readLine().split(" ");
       int SN = Integer.parseInt(line1[0]);
       int W = Integer.parseInt(line1[1]);
       for (int j = 0; j < SN; j++) {
         graph.get(i).add(new Station(i, j, W));
       }
       String[] dist = br.readLine().split(" ");
       for (int j = 0; j < dist.length; j++) {
         int d = Integer.parseInt(dist[j]);
         Station s1 = graph.get(i).get(j);
         Station s2 = graph.get(i).get(j + 1);
         s1.neighbors.put(s2, d);
         s2.neighbors.put(s1, d);
       }
     }
     int tunnelNum = Integer.parseInt(br.readLine());
     for (int i = 0; i < tunnelNum; i++) {
       String[] tunnel = br.readLine().split(" ");
       int l1 = Integer.parseInt(tunnel[0]) - 1;
       int s1 = Integer.parseInt(tunnel[1]) - 1;
       int l2 = Integer.parseInt(tunnel[2]) - 1;
       int s2 = Integer.parseInt(tunnel[3]) - 1;
       int d = Integer.parseInt(tunnel[4]);
       Station sta1 = graph.get(l1).get(s1);
       Station sta2 = graph.get(l2).get(s2);
       sta1.neighbors.put(sta2, d + sta2.waitTime); // add wait time to distance
       sta2.neighbors.put(sta1, d + sta1.waitTime);
       Station sta11 = sta1.cloneForTunnel();
       Station sta22 = sta2.cloneForTunnel();
       graph.get(sta1.lineNo).add(sta11);
       graph.get(sta2.lineNo).add(sta22);
       for (Station st : sta11.neighbors.keySet()) {
         sta2.neighbors.put(
             st,
             d
                 + sta11.neighbors.get(
                     st)); // don't wait, sta11 means go xsfrom sta2 to sta1 than go to other
         // tunnel
       }
       for (Station st : sta22.neighbors.keySet()) {
         sta1.neighbors.put(st, d + sta22.neighbors.get(st));
       }
     }
     int queryNum = Integer.parseInt(br.readLine());
     bw.write("Case: #" + t + ":");
     bw.newLine();
     for (int i = 0; i < queryNum; i++) {
       String[] query = br.readLine().split(" ");
       int l1 = Integer.parseInt(query[0]) - 1;
       int s1 = Integer.parseInt(query[1]) - 1;
       int l2 = Integer.parseInt(query[2]) - 1;
       int s2 = Integer.parseInt(query[3]) - 1;
       Station sta1 = graph.get(l1).get(s1);
       Station sta2 = graph.get(l2).get(s2);
       PriorityQueue<Station> pq = new PriorityQueue<>();
       sta1.dist = sta1.waitTime;
       for (List<Station> line : graph) {
         for (Station st : line) {
           pq.offer(st);
         }
       }
       Set<Station> visited = new HashSet<>();
       visited.add(sta1);
       boolean done = false;
       while (!done && !pq.isEmpty()) {
         Station st = pq.poll();
         for (Station neb : st.neighbors.keySet()) {
           if (!visited.contains(neb)) {
             neb.dist = st.dist + st.neighbors.get(neb);
             if (neb == sta2) { // reference to same object
               done = true;
               break;
             }
             visited.add(neb);
             pq.remove(neb); // because need to let pq update this item's priority level
             pq.offer(neb);
           }
         }
       }
       int ret = sta2.dist == Integer.MAX_VALUE ? -1 : sta2.dist;
       bw.write("" + ret);
       bw.newLine();
     }
   }
   bw.close();
   br.close();
 }
  public static void main(String[] args) throws Exception {
    int V, E, s, u, v, w;

    /* // Graph in Figure 4.17
    5 7 2
    2 1 2
    2 3 7
    2 0 6
    1 3 3
    1 4 6
    3 4 5
    0 4 1
        */

    Scanner sc = new Scanner(System.in);
    V = sc.nextInt();
    E = sc.nextInt();
    s = sc.nextInt();

    AdjList.clear();
    for (int i = 0; i < V; i++) {
      ArrayList<IntegerPair> Neighbor = new ArrayList<IntegerPair>();
      AdjList.add(Neighbor); // add neighbor list to Adjacency List
    }

    for (int i = 0; i < E; i++) {
      u = sc.nextInt();
      v = sc.nextInt();
      w = sc.nextInt();
      AdjList.get(u).add(new IntegerPair(v, w)); // first time using weight
    }

    // Dijkstra routine
    ArrayList<Integer> dist = new ArrayList<>();
    // INF = 1*10^9 not MAX_INT to avoid overflow
    dist.addAll(Collections.nCopies(V, INF));
    dist.set(s, 0);
    PriorityQueue<IntegerPair> pq =
        new PriorityQueue<IntegerPair>(
            1,
            new Comparator<IntegerPair>() { // overriding the compare method
              public int compare(IntegerPair i, IntegerPair j) {
                return i.dfs - j.dfs;
              }
            });
    pq.offer(new IntegerPair(s, 0)); // sort based on increasing distance

    while (!pq.isEmpty()) { // main loop
      IntegerPair top = pq.poll(); // greedy: pick shortest unvisited vertex
      int d = top.dfs;
      u = top.vn;
      if (d > dist.get(u)) continue; // We want to process vertex u only once!
      Iterator it = AdjList.get(u).iterator();
      while (it.hasNext()) { // all outgoing edges from u
        IntegerPair p = (IntegerPair) it.next();
        v = p.vn;
        int weight_u_v = p.dfs;
        if (dist.get(u) + weight_u_v < dist.get(v)) { // if can relax
          // (note: Record SP spanning tree here if needed. This is similar)
          dist.set(v, dist.get(u) + weight_u_v); // relax
          pq.offer(new IntegerPair(v, dist.get(v))); //   (as printpath in BFS)
          // enqueue this neighbor regardless whether it is already in pq or not
        }
      }
    }

    for (int i = 0; i < V; i++) // index + 1 for final answer
    System.out.printf("SSSP(%d, %d) = %d\n", s, i, dist.get(i));
  }
 public static void add(UrlValue url) {
   if (url != null && !url.url.trim().equals("") && !visitedUrl.contains(url.url)) {
     url.url = url.url.trim();
     pq.offer(url);
   }
 }