5211. 概率最大的路径（197）

Posted 2020-12-17 yonezu

 

 

class Solution {

    public double maxProbability(int n, int[][] edges, double[] succProb, int start, int end) {
        Map<Integer,List<Node>> map = new HashMap<>();
        for(int i = 0; i < edges.length; i++) {
            map.computeIfAbsent(edges[i][0],k->new ArrayList<>()).add(new Node(edges[i][1],succProb[i]));
            map.computeIfAbsent(edges[i][1],k->new ArrayList<>()).add(new Node(edges[i][0],succProb[i]));
        }
        Queue<Node> queue = new PriorityQueue<>((o1,o2)->Double.compare(o2.pro,o1.pro));
        queue.add(new Node(start,1.0));
        boolean[] st = new boolean[n];
        while(!queue.isEmpty()) {
            Node cur = queue.poll();
            if(cur.node == end) return cur.pro;
            if(!st[cur.node]) {
                st[cur.node] = true;
                List<Node> list = map.get(cur.node);
                if(list == null) continue;
                for(Node nn : list) {
                    queue.add(new Node(nn.node,nn.pro*cur.pro));
                }
            }
        }
        return 0;
    }
}

class Node {
    int node;
    double pro;
    public Node (int n, double p) {
        node = n;
        pro = p;
    }
}