只是记录

这题用迪杰斯特拉来就行，我写的是堆优化版本

import java.util.*;public class Main{static Scanner s = new Scanner(System.in);static int n,m,startPoint=1;static List<Edge>[] table;//邻接表,因为是稀疏图static long[] dist;static boolean[] used;public static void main(String[] args) {n = s.nextInt();m = s.nextInt();used = new boolean[n+1];dist = new long[n+1];table = new List[n+1];for(int i=0;i<=n;i++)table[i] = new ArrayList<>();for(int i=0;i<m;i++){int start = s.nextInt();int end = s.nextInt();long distance = s.nextLong();table[start].add(new Edge(end,distance));}dijkstra();for(int i=1;i<=n;i++){System.out.print(dist[i]==Long.MAX_VALUE?"-1 ":dist[i]+" ");}s.close();}static void dijkstra(){Arrays.fill(dist,Long.MAX_VALUE);dist[startPoint]=0;PriorityQueue<Edge> pq = new PriorityQueue<>((x,y)->x.distance.compareTo(y.distance));pq.add(new Edge(startPoint,0));while (!pq.isEmpty()){Edge poll = pq.poll();int t = poll.end;if(used[t])continue;used[t] = true;for(Edge item: table[t]){int vertex  = item.end;long distance = item.distance;if(!used[vertex] && dist[vertex] > dist[t]+distance){dist[vertex] = dist[t]+distance;pq.add(new Edge(vertex,dist[vertex]));}}}}
}
class Edge{int end;// 终点Long distance;//距离public Edge(int end,long distance){this.end = end;this.distance = distance;}
}