#include <iostream>
#include <string>
#include <vector>

using namespace std;

vector<int> string_to_vector_int(string s) {
    vector<int> v;
    for (auto c : s) {
        v.push_back(c - '0');
    }
    return v;
}

// använd denna datatyp för att skapa grafen
struct Node {
    int value;
    Node * grey_line;
    Node * red_line;
};

class Mod7 {
public:
    Mod7() {
        // Skapa grafen här
        for (int i{0}; i < 7; ++i)
            graph.push_back(new Node{i, nullptr, nullptr});
        for (int i{0}; i < 6; ++i)
            graph[i]->grey_line = graph[i+1];
        graph[6]->grey_line = graph[0];
        
        graph[0]->red_line = graph[0];
        graph[1]->red_line = graph[3];
        graph[2]->red_line = graph[6];
        graph[3]->red_line = graph[2];
        graph[4]->red_line = graph[5];
        graph[5]->red_line = graph[1];
        graph[6]->red_line = graph[4];
    }

    ~Mod7(){
        for (Node* n : graph)
            delete n;
    }
    
    int remainder(string number) {
        // Implementera algoritmen här
        
        Node* current{graph[0]};
        vector<int> digits{string_to_vector_int(number)};
        for (int i{0}; i < digits.size(); ++i)
        {
            for (int j{digits[i]}; j > 0; --j)
                current = current->grey_line;
            if (i + 1 < digits.size())
                current = current->red_line;
        }
        return current->value;
    }

private:

    // Lägg eventuella datamedlemmar här
    std::vector<Node*> graph;
};


int main() {
    string test1{"243"};

    Mod7 modder{};

    if (modder.remainder("243") == 5) {
        cout << "Stämmer!" << endl;
    }

    if (modder.remainder("11111111111111111111111111111") == 2) {
        cout << "Stämmer!" << endl;
    }

    if (modder.remainder("4221") == 0) {
        cout << "Stämmer!" << endl;
    }
}