#include <vector>
#include <iostream>

using namespace std;

class Solution {
public:
    vector<vector<int>> generate(int numRows) {
        vector<vector<int>> result{};

        if (numRows == 0) {
            return result;
        }
        else {
            vector<int> temp{1};
            result.push_back(temp);
            helper(result, numRows);
            return result;
        }
    }

    void helper(vector<vector<int>> &result, int numRows) {
        vector<int> current = result[result.size() - 1];

        if (current.size() == numRows)
            return;

        vector<int> nextArray{1};

        auto current_it = current.begin();
        while(1) {
            if ((current_it + 1) == current.end()) {
                nextArray.push_back(1);
                break;
            }
            int current_val = *current_it++;
            int next_val = *current_it;
            nextArray.push_back(current_val + next_val);
        }
        result.push_back(nextArray);

        helper(result, numRows);
    }
};

int main(int argc, char**argv) {
    auto obj = Solution();
    vector<vector<int>> result = obj.generate(10);

    for (auto it = result.begin(); it != result.end(); ++it) {
        vector<int> current = *it;
        for (auto it = current.begin(); it != current.end(); ++it) {
            cout << *it << ',';
        }
        cout << endl;
    }

    return 0;
}