TBB(LevelGraph& graph, unsigned num_threads) {

tbb::task_scheduler_init init(num_threads);

tasks.resize(graph.level());

for(size_t i=0; i<tasks.size(); ++i) {

tasks[i].resize(graph.length());

}

for(size_t i=0; i<graph.length(); i++){

Node& n = graph.node_at(graph.level()-1, i);

tasks[graph.level()-1][i] = std::make_unique<continue_node<continue_msg>>(G,

[&](const continue_msg&){ n.mark(); }

);

}

for(int l=graph.level()-2; l>=0 ; l--){

for(size_t i=0; i<graph.length(); i++){

Node& n = graph.node_at(l, i);

tasks[l][i] = std::make_unique<continue_node<continue_msg>>(G,

[&](const continue_msg&){ n.mark(); }

);

for(size_t k=0; k<n._out_edges.size(); k++){

make_edge(*tasks[l][i], *tasks[l+1][n._out_edges[k]]);

}

}

}

source = std::make_unique<continue_node<continue_msg>>(G,

[](const continue_msg&){}

);

for(int l=0; l>=0 ; l--) {

for(size_t i=0; i<graph.length(); i++){

make_edge(*source, *tasks[l][i]);

}

}

}

void run() {

source->try_put(continue_msg());

G.wait_for_all();

}

tbb::flow::graph G;

std::vector<std::vector<std::unique_ptr<continue_node<continue_msg>>>> tasks;

std::unique_ptr<continue_node<continue_msg>> source;

TBB tbb(graph, num_threads);

for(auto i=0; i<repeat; i++) {

tbb.run();

graph.clear_graph();

}

auto beg = std::chrono::high_resolution_clock::now();

traverse_regular_graph_tbb(graph, num_threads, repeat);

auto end = std::chrono::high_resolution_clock::now();

return std::chrono::duration_cast<std::chrono::microseconds>(end - beg);