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Cod sursa(job #484942)
#include <fstream>
#include <limits>
#include <set>
#include <vector>
#include <utility>
int main()
{
std::ifstream in("dijkstra.in");
std::ofstream out("dijkstra.out");
std::vector<std::vector<int> > arcs, graph;
// Read the number of nodes and arcs.
int nodeCount, arcCount;
in >> nodeCount >> arcCount;
// Make sure we have enough space.
graph.resize(arcCount);
arcs.resize(arcCount);
// Populate the vectors with the nodes and arcs.
for (int i = 1; i <= arcCount; i++)
{
int sourceNode, targetNode, arcLength;
in >> sourceNode >> targetNode >> arcLength;
graph.at(sourceNode).push_back(targetNode);
arcs.at(sourceNode).push_back(arcLength);
}
std::vector<int> distances(nodeCount + 1, std::numeric_limits<int>::max());
std::set<std::pair<int, int> > targets;
targets.insert(std::make_pair(0, 1));
while (targets.size() > 0)
{
int val = (*targets.begin()).first;
int x = (*targets.begin()).second;
targets.erase(*targets.begin());
for (int i = 0; i < static_cast<int>(graph.at(x).size()); i++)
{
if (distances.at(graph.at(x).at(i)) > val + arcs.at(x).at(i))
{
distances.at(graph.at(x).at(i)) = val + arcs.at(x).at(i);
targets.insert(std::make_pair(distances.at(graph.at(x).at(i)), graph.at(x).at(i)));
}
}
}
// Output the results.
for (int i = 2; i <= nodeCount; i++)
out << ((distances.at(i) == INT_MAX) ? 0 : distances.at(i)) << ' ';
}