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#include <bits/stdc++.h>
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
const int NMAX = 50001;
#define infinit 2e9
struct State
{
int node, cost;
bool operator< (const State& other) const
{
/// State o sa fie integrat intr-un priority queue
/// ne propunem sa construim un min-heap de state-uri
return cost > other.cost;
}
};
vector <pair<int, int>> graph[NMAX];
int best_dist[NMAX];
int n, m, cost;
priority_queue<State> pq;
void read()
{
int x, y;
fin>>n>>m;
for(int i=1; i<=n; i++)
{
best_dist[i]=infinit;
}
for(int i = 1; i <= m; ++i)
{
fin>>x>>y>>cost;
graph[x].push_back({y, cost});
}
}
void dijkstra(int source)
{
int node,cost;
best_dist[source]=0;
pq.push({source,0});
while(!pq.empty())
{
node=pq.top().node;
cost=pq.top().cost;
pq.pop();
if(best_dist[node] < cost)
{
continue;
}
/// range-based for-loop
/// pentru fiecare 'neighbour' din graph[node]
/// executa ...
for (auto edge: graph[node])
{
int neighbour = edge.first;
int edge_cost = edge.second;
if( best_dist[neighbour] > cost+edge_cost)
{
best_dist[neighbour]=cost+edge_cost;
pq.push({neighbour,best_dist[neighbour]});
}
}
}
}
void print()
{
for (int i = 2; i <= n; ++i)
{
if (best_dist[i] == infinit)
{
fout << 0 << ' ';
}
else
{
fout << best_dist[i] << ' ';
}
}
}
int main()
{
read();
dijkstra(1);
print();
return 0;
}