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 x k cost matrix. For example, costs is the cost of painting house 0 with color 0; costs is the cost of painting house 1 with color 2, and so on… Find the minimum cost to paint all houses.