【发布时间】:2017-02-10 21:30:11
【问题描述】:
我正在尝试使用 Dijkstra 算法来找到图中两个节点之间的最短路径。
当找到源和目标之间的最短路径时,我应该如何处理以下代码以停止计算?
public void calculate(Vertex source){
// Algo:
// 1. Take the unvisited node with minimum weight.
// 2. Visit all its neighbours.
// 3. Update the distances for all the neighbours (In the Priority Queue).
// Repeat the process till all the connected nodes are visited.
source.minDistance = 0;
PriorityQueue<Vertex> queue = new PriorityQueue<Vertex>();
queue.add(source);
while(!queue.isEmpty()){
Vertex u = queue.poll();
for(Edge neighbour:u.neighbours){
Double newDist = u.minDistance+neighbour.weight;
if(neighbour.target.minDistance>newDist){
// Remove the node from the queue to update the distance value.
queue.remove(neighbour.target);
neighbour.target.minDistance = newDist;
// Take the path visited till now and add the new node.s
neighbour.target.path = new LinkedList<Vertex>(u.path);
neighbour.target.path.add(u);
//Reenter the node with new distance.
queue.add(neighbour.target);
}
}
}
}
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