예제 #1
0
  /**
   * Algorithm of Tarjan for computing the strongly connected components of a graph.
   *
   * @param v current node
   * @throws QueryException if a variable directly calls itself
   */
  private void tarjan(final int v) throws QueryException {
    final int ixv = 2 * v, llv = ixv + 1, idx = next++;
    while (list.size() <= llv) list.add(-1);
    list.set(ixv, idx);
    list.set(llv, idx);

    stack.push(v);

    for (final int w : adjacentTo(v)) {
      final int ixw = 2 * w, llw = ixw + 1;
      if (list.size() <= ixw || list.get(ixw) < 0) {
        // Successor w has not yet been visited; recurse on it
        tarjan(w);
        list.set(llv, Math.min(list.get(llv), list.get(llw)));
      } else if (stack.contains(w)) {
        // Successor w is in stack S and hence in the current SCC
        list.set(llv, Math.min(list.get(llv), list.get(ixw)));
      }
    }

    // If v is a root node, pop the stack and generate an SCC
    if (list.get(llv) == list.get(ixv)) {
      int w;
      Scope[] out = null;
      do {
        w = stack.pop();
        final Scope scp = scopes.get(w);
        out = out == null ? new Scope[] {scp} : Array.add(out, scp);
      } while (w != v);
      result.add(out);
    }
  }
예제 #2
0
 /**
  * Finds line and column for the specified query parser.
  *
  * @param parser parser
  */
 void pos(final InputParser parser) {
   markedCol = parser.mark;
   if (info != null) return;
   // check if line/column information has already been added
   parser.pos = Math.min(parser.mark, parser.length);
   info = new InputInfo(parser);
 }
예제 #3
0
파일: ADate.java 프로젝트: jefferya/basex
  /**
   * Adds/subtracts the specified yearMonth duration.
   *
   * @param dur duration
   * @param plus plus/minus flag
   * @param ii input info
   * @throws QueryException query exception
   */
  final void calc(final YMDur dur, final boolean plus, final InputInfo ii) throws QueryException {
    final long m = plus ? dur.mon : -dur.mon;
    final long mn = mon + m;
    mon = (byte) mod(mn, 12);
    yea += div(mn, 12);
    day = (byte) Math.min(dpm(yea, mon) - 1, day);

    if (yea <= MIN_YEAR || yea > MAX_YEAR) throw YEARRANGE_X.get(ii, yea);
  }