problem 1

ladder.cxx

int step(int curr, int steps, const int n)
{
    curr += steps;
    if (curr < n)
        return step(curr, 1, n) + step(curr, 2, n);
    if (curr == n)
        return 1;
    
    return 0;
}

int main()
{
    const int n; // whatever.
    if (n < 1) { 
        std::cout << "Not possible to climb this ladder" << std::endl;
        return 1; // bad n
    }

    int steps = step(0, 1, n) + step(0, 2, n);
    std::cout << "Total ways of climbing ladder: " << steps << std::endl;

    return 0;
}