gabi e sladka

#include <iostream>
#include <list>
#include <stack>
#include <string>

using namespace std;

bool allArePresent(list<string> &base, list<string> &elements)
{
    for (auto &el : elements)
    {
        bool found = false;
        for (auto &el2 : base)
        {
            if (el2 == el)
            {
                found = true;
            }
        }
        if (!found)
        {
            return false;
        }
    }
    return true;
}

void addIfAbsent(list<string> &l, list<string> &elements)
{
    for (auto el : elements)
    {
        bool found = false;
        for (auto &res_el : l)
        {
            if (res_el == el)
            {
                found = true;
                break;
            }
        }
        if (!found)
        {
            l.push_back(el);
        }
    }
}

bool addIfAbsent(list<string> &list, string el)
{
    bool found = false;
    for (auto &res_el : list)
    {
        if (res_el == el)
        {
            found = true;
            break;
        }
    }
    if (!found)
    {
        list.push_back(el);
        return true;
    }
    return false;
}

list<string> getSurroundingStations(const list<list<string>> &lines, string station)
{
    list<string> result;
    for (const list<string> &el : lines)
    {
        string prev = "";
        auto it = el.begin();
        while (it != el.end())
        {
            if (*it == station)
            {
                if (!prev.empty())
                {
                    addIfAbsent(result, prev);
                }
                it++;
                if (it != el.end())
                {
                    addIfAbsent(result, *it);
                }
                break;
            }
            else
            {
                prev = *it;
            }
            it++;
        }
    }

    return result;
}

void printStack(stack<string> st)
{
    while (!st.empty())
    {
        cout << st.top() << ' ';
        st.pop();
    }
    cout << '\n';
}

void printList(list<string> l)
{
    for (auto &el : l)
    {
        cout << el << ' ';
    }
    cout << endl;
}

list<string> getPath(const list<list<string>> &lines, const string &origin, const string &destination)
{
    list<string> visited;
    list<string> path;
    stack<string> st;
    path.push_back(origin);
    visited.push_back(origin);
    st.push(origin);

    while (!st.empty() && path.back() != destination)
    {
        cout << "List: ";
        printList(path);
        cout << "Stack: ";
        printStack(st);
        cout << endl;

        list<string> current = getSurroundingStations(lines, st.top());
        if (allArePresent(visited, current))
        {
            if (!st.empty())
            {
                st.pop();
            }
            if (!path.empty())
            {
                path.pop_back();
            }
        }
        else
        {
            if (path.back() != st.top())
            {
                path.push_back(st.top());
            }

            for (auto &el : current)
            {
                if (addIfAbsent(visited, el))
                {
                    st.push(el);
                }
                if (st.top() == destination)
                {
                    path.push_back(destination);
                    break;
                }
            }

            if (path.back() != st.top())
            {
                path.push_back(st.top());
            }
        }
    }

    return path;
}

int main()
{
    list<list<string>> lines = {{"Stranraer", "Glasgow Central", "Falkirk High", "Edinburgh"},
                                {"Fort William", "Glasgow Central", "Edinburgh", "Newcastle", "York", "Doncaster", "Peterborough", "London KingsX"},
                                {"Bangor", "Chester", "Crewe", "Nottingham", "Peterborough", "Norwich"},
                                {"Norwich", "Cambridge", "Hitchin", "London KingsX"},
                                {"Penzance", "Plymouth", "Exeter", "Swindon", "London Victoria"}};

    list<string> path = getPath(lines, "Stranraer", "Norwich");

    for (auto &el : path)
    {
        cout << el << ' ';
    }
    return 0;
}