コード例 #1
0
ファイル: Graph.cpp プロジェクト: jk983294/Store
void Graph::dijkstra_shortest_path(int root, bool isTerminateAsFound){
	//<length nodeid > tricky nodes[i]为节点i在heap中的指针 
	MinBinaryHeap<int, int > q;  //优先队列	
	vector <BinaryHeapNode<int, int >*> nodes(n);   	
	int min,w;		//min 最小权值对应的节点id, w为与min相连的节点id
	for (int i = 0; i < n; ++i){
		distance[i] = POSTIVE_MAXINT;     parent[i] = -1;
		if ( i == root ) { distance[i] = 0; parent[i] = i; }
		nodes[i] = q.insert(distance[i],i);
	}
	while(!q.empty()){
		min = q.minimum()->data();
		if (isTerminateAsFound  && min==dest){	//必须等到dest出优先队列才能结束,因为以后都不可能对其松弛
			break;
		}	
		if (q.minimum()->key() == POSTIVE_MAXINT){	break;	}	//后面的都是其他森林,不需要遍历
		q.removeMinimum();  nodes[min] = NULL;
		//开始更新和u相连的边 relax
		list<Node>::iterator itr = linktable[min].begin();
		while(itr !=  linktable[min].end()){
			w = itr->id;
			if (nodes[w] != NULL)   //未被选中加入S
			{
				if (distance[min]+itr->weight < distance[w])    //relax
				{
					q.decreaseKey(nodes[w], distance[min]+itr->weight);
					distance[w] = distance[min]+itr->weight;
					parent[w] = min;
				}
			}
			++itr;
		}
	}
}
コード例 #2
0
ファイル: Graph.cpp プロジェクト: jk983294/Store
void Graph::dijkstra_without_pass_other_mustpass_nodes(int root){
	//<length nodeid > tricky nodes[i]为节点i在heap中的指针 
	MinBinaryHeap<int, int > q;  //优先队列	
	vector <BinaryHeapNode<int, int >*> nodes(n);   	
	int min,w;		//min 最小权值对应的节点id, w为与min相连的节点id
	for (int i = 0; i < n; ++i){
		distance[i] = POSTIVE_MAXINT;     parent[i] = -1;
		if ( i == root ) { distance[i] = 0; parent[i] = i; }
		nodes[i] = q.insert(distance[i],i);
	}
	while(!q.empty()){
		min = q.minimum()->data();
//		if (min==end)	break;		//必须等到end出优先队列才能结束,因为以后都不可能对其松弛
		if (q.minimum()->key() == POSTIVE_MAXINT){	break;	}	//后面的都是其他森林,不需要遍历
		q.removeMinimum();  nodes[min] = NULL;
		//除root以外其他必过节点成为黑洞,没有出边,不帮助松弛
		if ((min != root )&&(allmustpass.find(min) != allmustpass.end()))	continue;	
		//开始更新和u相连的边 relax
		list<Node>::iterator itr = linktable[min].begin();
		while(itr !=  linktable[min].end()){
			w = itr->id;
			if (nodes[w] != NULL){   //未被选中加入S
				if (distance[min]+itr->weight < distance[w]){    //relax
					q.decreaseKey(nodes[w], distance[min]+itr->weight);
					distance[w] = distance[min]+itr->weight;
					parent[w] = min;
				}
			}
			++itr;
		}
	}
}
コード例 #3
0
bool test_insert_deleteMin(int numItems) {
  MinBinaryHeap h;
  bool failed = false;
  int i;

  for (i = 0; i < numItems; i++) {
    h.insert(new IntegerData(i));
  }
  for(i = 0; i < numItems; i++ ) {
    IntegerData * x = (IntegerData*)h.deleteMin();

    if( x->value != i ) {
      cout << "Oops! " << i << " != " << x->value << endl;
      failed = true;
    }
    delete x;
  }
  if (failed) {
    cout << "insert/remove 0:9999 failed" << endl;
  }
  else {
    cout << "insert/remove 0:9999 successful" << endl;
  }

  return failed;
}
コード例 #4
0
bool test_random(int numItems) {
  MinBinaryHeap h;
  Container ** nodePointers = new Container * [numItems];
  IntegerData ** values = new IntegerData * [numItems];
  bool failed = false;
  int i;

  for (i = 0; i < numItems; i++) {
    // need to be careful not to work with data that is near integer max or min value
    values[i] = new IntegerData(rand() % numItems);
    nodePointers[i] = h.insert(values[i]);
  }

  failed = false;
  for (i = 0; i < numItems; i++) {
    // need to be careful not to work with data that is near integer max or min value
    // because if we subtract from min or add to max we get overflow (undefined behavior)
    if (i % 2 == 0) {
      values[i]->value -= rand() % numItems;
      h.decreaseKey(nodePointers[i]);
    }
    else {
      values[i]->value += rand() % numItems;
      h.increaseKey(nodePointers[i]);
    }
  }
  IntegerData * x = (IntegerData*)h.deleteMin();
  int lastValue = x->value;
  delete x;
  for(i = 1; i < numItems; i++ ) {
    x = (IntegerData*)h.deleteMin();

    if( x->value < lastValue ) {
      cout << "Oops! " << x->value << " is not >= " << lastValue << endl;
      failed = true;
    }
    lastValue = x->value;

    delete x;
  }
  if (failed) {
    cout << "random test failed" << endl;
  }
  else {
    cout << "random test successful" << endl;
  }

  delete [] nodePointers;
  delete [] values;

  return failed;
}
コード例 #5
0
bool test_increase_decreaseKey(int numItems) {
  MinBinaryHeap h;
  Container ** nodePointers = new Container * [numItems];
  IntegerData ** values = new IntegerData * [numItems];
  bool failed = false;
  int i;

  for (i = 0; i < numItems; i++) {
    values[i] = new IntegerData(i);
    nodePointers[i] = h.insert(values[i]);
  }

  failed = false;
  for (i = 0; i < numItems; i++) {
    // decrease all the even ones by 1, increase all the odd ones by 9998
    // should result in the sequence -1, 1, 3, ..., 9995, 9997, (odds + 9998)=9999, 10001...
    if (i % 2 == 0) {
      values[i]->value--;
      h.decreaseKey(nodePointers[i]);
    }
    else {
      values[i]->value+=9998;
      h.increaseKey(nodePointers[i]);
    }
  }

  for(i = 0; i < numItems; i++ ) {
    IntegerData * x = (IntegerData*)h.deleteMin();

    if( x->value != (i*2-1) ) {
      cout << "Oops! " << (i*2-1) << " != " << x->value << endl;
      failed = true;
    }
    delete x;
  }
  if (failed) {
    cout << "decreaseKey evens/increaseKey odds 0:9999 failed" << endl;
  }
  else {
    cout << "decreaseKey evens/increaseKey odds 0:9999 successful" << endl;
  }

  delete [] nodePointers;
  delete [] values;

  return failed;
}