/*
    prawie posortowana tablica, co najmniej 2 elementy, jeden losowy podmieniony losowo
    trzeba poprawić
*/

struct Node {
    Node *next;
    int value;
};

bool isUp(node* first) {
    if (first == nullptr)
        return true;
    int up=0, down=0;
    for (int i=0; i<4 && first->next != nullptr; i++, first = first->next)
        if (first->val < first->next->val)
            up++;
        else
            down++;
    return up > down;
}

void fixSortedList(Node *&L) {
    if (L == nullptr || L->next == nullptr || L->next->next == nullptr)
        return;

    bool up = isUp(L);

    node* guard = new Node;
    guard->next = L;

    Node* diff = nullptr
    if ((up && L->value > L->next->value) || (!up && L->value < L->next->value)) {
        diff = L;
        guard->next = L->next;
    } else {
        while ((up && L->value < L->next->value) || (!up && L->value > L->next->value))
            L = L->next;
        diff = L->next;
        L->next = diff->next;
    }
    if (diff != nullptr) {
        L = guard;
        while ((up && L->next->value < diff->value ) || (!up && L->next->value > diff->value))
            L = L->next;
        diff->next = L->next;
        L->next = diff->next;
    }
    L = guard->next;
    delete guard;
}