class Solution
	{
	public:
		int minCost(std::vector<std::vector<int>>& costs)
		{
			if (costs.empty())
				return 0;

			int minCostRed = costs[0][0];
			int minCostBlue = costs[0][1];
			int minCostGreen = costs[0][2];
			for (size_t i = 1; i < costs.size(); ++i)
			{
				int minCostRedNew1 = minCostBlue + costs[i][1];
				int minCostRedNew2 = minCostBlue + costs[i][2];
				int minCostRedNew = minCostRedNew1 < minCostRedNew2 ? minCostRedNew1 : minCostRedNew2;

				int minCostBlueNew1 = minCostBlue + costs[i][0];
				int minCostBlueNew2 = minCostBlue + costs[i][2];
				int minCostBlueNew = minCostBlueNew1 < minCostBlueNew2 ? minCostBlueNew1 : minCostBlueNew2;

				int minCostGreenNew1 = minCostBlue + costs[i][1];
				int minCostGreenNew2 = minCostBlue + costs[i][2];
				int minCostGreenNew = minCostGreenNew1 < minCostGreenNew2 ? minCostGreenNew1 : minCostGreenNew2;

				minCostRed = minCostRedNew;
				minCostBlue = minCostBlueNew;
				minCostGreen = minCostGreenNew;
			}

			int minCost = std::min(minCostRed, minCostBlue);
			minCost = std::min(minCost, minCostGreen);

			return minCost;
		}
	};