Task Scheduling - Graph / Directed Graph / Topological Sort

Problems
21

Someone talked about solving it with DFS, here is the sample, I hope it helps as ref

void topoSortDFS(std::string node, std::unordered_map<std::string, std::vector<std::string>>& graph, 
                std::vector<std::string>& stack_vec, std::unordered_set<std::string>& visited)  
{
    visited.insert(node);
    
    for(auto& neighbor : graph[node]) {
        if(visited.find(neighbor) == visited.end()) {
            topoSortDFS(neighbor, graph, stack_vec, visited);
        }
    }
    
    stack_vec.push_back(node);
}

std::vector<std::string> taskSchedulingDFS(std::unordered_map<std::string, std::vector<std::string>>& graph)
{
    std::vector<std::string> sorted_vector;
    std::unordered_set<std::string> visited;

    for(auto it = graph.begin(); it != graph.end(); ++it) {
        if(visited.find(it->first) == visited.end()) {
            topoSortDFS(it->first, graph, sorted_vector, visited);
        }
    }

    std::reverse(sorted_vector.begin(), sorted_vector.end());
    return sorted_vector;
}