There are a row of n houses, each house can be painted with one of the k colors. The cost of painting each house with a certain color is different. You have to paint all the houses such that no two adjacent houses have the same color.
The cost of painting each house with a certain color is represented by a n * k cost matrix.
For example, costs[0][0] is the cost of painting house 0 with color 0; costs[1][2] is the cost of painting house 1 with color 2, and so on...
Find the minimum cost to paint all houses.
Note: All costs are positive integers.
Follow up: Could you solve it in O(nk) runtime?
DP with state savings, dont need all n * k states
For each iteration over 'house', get the max and min for previous houses:
dp[i][j]= (dp[i-1][j] == preMin ? preSecondMin : preMin) + costs[i][j]