Dijkstra Java

https://leetcode.com/problems/network-delay-time/

 

/* Java program to find a Pair which has maximum score*/
import javafx.util.Pair;

class Solution {
    
    
    public int networkDelayTime(int[][] times, int N, int K) {
        
        Map<Integer,List<int[]>> graph = new HashMap<>();
        
        for(int[] edge:times)
        {
            if(!graph.containsKey(edge[0]))
                graph.put(edge[0],new ArrayList<int[]>());
            graph.get(edge[0]).add(new int[]{edge[1],edge[2]});
        }
        
        Map<Integer,Integer> node_dis = new HashMap<>();
        
        for(int i =1;i<=N;i++)
            node_dis.put(i,Integer.MAX_VALUE);
        node_dis.put(K,0);
        
        boolean[] seen = new boolean[N+1];
        
        while(true)
        {
            int curNode = -1;
            //find the nearest node
            int curDis = Integer.MAX_VALUE;
            for(int i =1;i<=N;i++)
            {
                if(!seen[i] && node_dis.get(i)<curDis)
                {
                    curDis = node_dis.get(i);
                    curNode = i;
                }
            }
            
            if(curNode==-1) break;
            seen[curNode] = true;
            if(graph.containsKey(curNode))
                for(int[] pair: graph.get(curNode))
                {
                    node_dis.put(pair[0],Math.min(node_dis.get(pair[0]), curDis+pair[1]));
                }
        }
        
        
        int res =0;
        for(int d: node_dis.values())
        {
            if(d==Integer.MAX_VALUE) return -1;
            res = Math.max(res,d);
        }
        
        
        return res;
    }
}