solve.cpp

#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
class Solution {
	public:
		vector<vector<int>> subsets(vector<int> &nums) {
			return subsets_iterative(nums);
		}
	private:
		vector<vector<int>> subsets_recurisive(vector<int> &nums) {
			vector<vector<int>> result;
			vector<int> cur;
			sort(nums.begin(), nums.end());
			subsets_recurisive(result, cur, nums, 0);
			return result;
		}
		void subsets_recurisive(vector<vector<int>> &result, vector<int> cur, const vector<int> &nums, int i) {
			if (i == nums.size()) {
				result.push_back(cur);
				return;
			}
			subsets_recurisive(result, cur, nums, i + 1);
			cur.push_back(nums[i]);
			subsets_recurisive(result, cur, nums, i + 1);
		}
		vector<vector<int>> subsets_iterative(vector<int> &nums) {
			vector<vector<int>> result(1, vector<int>());
			sort(begin(nums), end(nums));
			int n = nums.size();
			for (int i = 0; i < n; ++i) {
				int m = result.size();
				for (int j = 0; j < m; ++j) {
					result.push_back(result[j]);
					result.back().push_back(nums[i]);
				}
			}
			return result;
		}
};
void print(vector<vector<int>> nums)
{
	for (auto v : nums) {
		cout << "[";
		for_each(begin(v), end(v), [](int i){cout << i << ",";});
		cout << "]";
		cout << endl;
	}
}
int main(int argc, char **argv)
{
	Solution solution;
	vector<int> nums = {4,1,0};
	print(solution.subsets(nums));
	return 0;
}