class Graph{
    public:


        Graph(int size) : visited(size, false){
            for(int i = 0; i < size; ++i){
                matrix.push_back(vector<int>(size,0));
                string s;
                cout << "Enter name v : ";
                cin >> s;
                ItN.push_back(s);
                NtI[s] = i;
            }
        }

        auto First(string v){
            if(!matrix[NtI[v]].empty()){
                if(NtI[v] >= matrix.size())
                    throw runtime_error("going beyond the boundaries of the matrix");
                else{
                    for(int i = 0; i < matrix[NtI[v]].size(); ++i){
                        if(matrix[NtI[v]][i] != 0)
                            return i;
                    }
                    return -1;
                }
            } else
                throw runtime_error("height does not exist");
        }

        auto Next(string v, int i){
            if(!matrix[NtI[v]].empty()){
                if(i == matrix[NtI[v]].size() - 1){
                    return -1;
                }
                for(int x = i + 1; i < matrix[0].size(); ++i){
                    if(matrix[NtI[v]][x] != 0)
                        return x;
                }
                return -1;
            }
            else
                throw runtime_error("height does not exist");
        }

        string Vertex(string v, int i) {
            if(!matrix[NtI[v]].empty()){
                if (matrix[NtI[v]][i])
                    return ItN[i];
            }
            else throw runtime_error("height does not exist");

        }

        void Add_V(string v){
            NtI[v] = matrix.size();
            ItN.push_back(v);
            matrix.push_back(vector<int>(matrix[0].size(), 0));
            for(auto& x : matrix) {
                if(!x.empty())
                    x.push_back(0);
            }
        }

        void Add_E(string v, string w, int c){
            matrix[NtI[v]][NtI[w]] = c;
        }

        void Del_V(string v){
            int index = NtI[v];
            matrix.erase(matrix.begin() + index);
            visited.erase(visited.begin() + index);
            ItN.erase(ItN.begin() + index);
            NtI.erase(v);
            for(int i = 0; i < matrix.size(); ++i)
                matrix.erase(matrix.begin() + index);
            for (auto& x : NtI)
                if (x.second > index)
                    --x.second;
        }

        auto Del_E(string v, string w){
            matrix[NtI[v]][NtI[w]] = 0;
        }

        auto Edit_V(string v, bool mark){
            visited[NtI[v]] = mark;
        }

        auto Edit_E(string v, string w, int c){
            matrix[NtI[v]][NtI[w]] = c;
        }

        auto print(){
            cout << endl;
            for(int i = 0; i < matrix.size(); ++i){
                if(!matrix[i].empty()) {
                    for (int j = 0; j < matrix[i].size(); ++j) {
                        cout << matrix[i][j] << ' ';
                    }
                    cout << endl;
                }

            }
        }

        auto GetWeight(string first, string second) {
            long long i = NtI[first], j = NtI[second];
            if (i < matrix.size() && j < matrix.size())
                return matrix[i][j];
            else throw runtime_error("l");
        }

        bool IsVisited(string node) {
            return visited[NtI[node]];
        }

    private:

        vector<bool> visited;
        vector<vector<int>> matrix;
        map<string, int> NtI;
        vector<string> ItN;

    };