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#include <bits/stdc++.h>
struct edge
{
int v, cost;
};
int nodes, edges, u, v, cost;
std :: vector<edge> adj[50001];
int distance[50001], OO = 20001;
struct orderByDistance
{
bool operator()(int a, int b)
{
return distance[a] > distance[b];
}
};
std :: priority_queue<int, std :: vector<int>, orderByDistance> q;
void Dijkstra(int start)
{
for(int i = 1; i <= nodes; i++)
{
distance[i] = i == start ? 0 : OO;
q.push(i);
}
while(!q.empty())
{
int u = q.top(); q.pop();
for(edge i : adj[u])
{
int v = i.v, cost = i.cost;
if(distance[v] > distance[u] + cost)
{
distance[v] = distance[u] + cost;
}
}
}
}
int main()
{
freopen("dijkstra.in", "r", stdin);
freopen("dijkstra.out", "w", stdout);
scanf("%d %d", &nodes, &edges);
for(int i = 1; i <= edges; i++)
{
scanf("%d %d %d", &u, &v, &cost);
adj[u].push_back({v, cost});
}
Dijkstra(1);
for(int i = 2; i <= nodes; i++)
{
printf("%d ", distance[i] == OO ? 0 : distance[i]);
}
return 0;
}
///function Dijkstra(Graph, source):
/// create vertex set Q
/// for each vertex v in Graph: // Initialization
/// dist[v] ← INFINITY // Unknown distance from source to v
/// prev[v] ← UNDEFINED // Previous node in optimal path from source
/// add v to Q // All nodes initially in Q (unvisited nodes)
/// dist[source] ← 0 // Distance from source to source
/// while Q is not empty:
/// u ← vertex in Q with min dist[u] // Node with the least distance will be selected first
/// remove u from Q
/// for each neighbor v of u: // where v is still in Q.
/// alt ← dist[u] + length(u, v)
/// if alt < dist[v]: // A shorter path to v has been found
/// dist[v] ← alt
/// prev[v] ← u
/// return dist[], prev[]