Challenge #242 - Easy

#include <iostream>
#include <vector>

using namespace std;

int Calc(int a, int b, vector<int> &c, int w = 0); //a = people, b = initial fruits, c = "harvest" vector, w = weeks

int main()
{
    int a, b, d;
    cout << "Number of people:";
    cin >> a;
    cout << endl << "Initial fruits:";
    cin >> b;
    if(a <= b)
    {
        cout << endl << "You already have enough fruits, duh";
        return 0;
    }

    vector<int> c;

    for(int _a = 0; _a < b;_a++) c.push_back(0); //fills our harvest vector

    d = Calc(a,b,c,1);
    cout << endl << "Weeks needed:" << d;

    return 0;
}

int Calc(int a, int b, vector<int> &c, int w) //a = people, b = fruits currently planted, c = "harvest" vector, w = weeks
{
    ++w;
    int d = 0;
    for(int i = 0; i < b; i++)
    {
        c[i]++;
        d+= c[i];
    }
    if(d >= a) return w;
    else
    {
        for(int i = 0; i < d; i++)
        {
            c.push_back(0);
        }
        Calc(a,b+d, c, w);
    }
}