Sword finger offer II 091 Paint the house

Original link ： The finger of the sword Offer II 091. Paint the house

solution:

        Simple dp

class Solution {
public:
    int minCost(vector<vector<int>>& costs) {
        int n = costs.size();
        vector<vector<int>> dp(n + 1, vector<int> (3));
        //dp[i][j] It means to put in front of i House dyeing , The first i A house is dyed j Minimum cost of color 
        //0: Red  1: Blue  2: green 
        dp[1][0] = costs[0][0];
        dp[1][1] = costs[0][1];
        dp[1][2] = costs[0][2];

        for(int i = 2;i <= n;i++) {
            dp[i][0] = min(dp[i - 1][1], dp[i - 1][2]) + costs[i - 1][0];
            dp[i][1] = min(dp[i - 1][0], dp[i - 1][2]) + costs[i - 1][1];
            dp[i][2] = min(dp[i - 1][0], dp[i - 1][1]) + costs[i - 1][2];
        }

        return min(min(dp[n][0], dp[n][1]), dp[n][2]);
    }
};