Java: PriorityQueue returning incorrect ordering from custom comparator??
- by Michael Simpson
I've written a custom comparator to compare my node classes, but the java priority queue is not returning my items in the correct order.
Here is my comparator:
public int compare(Node n1, Node n2){
if (n1.getF() > n2.getF()){
return +1;
}
else if (n1.getF() < n2.getF()){
return -1;
}
else { // equal
return 0;
}
}
Where getF returns a double. However after inserting several Nodes into the priority queue, I print them out using:
while(open.size() > 0) {
Node t = (Node)(open.remove());
System.out.println(t.getF());
}
Which results in:
6.830951894845301
6.830951894845301
6.0
6.0
5.242640687119285
7.4031242374328485
7.4031242374328485
8.071067811865476
Any ideas why this is so? Is my comparator wrong? Thanks.
Mike
