Paint House

想想想

public class Solution {
    public int minCost(int[][] costs) {
        if (costs == null || costs.length == 0) {
    		return 0;
    	}  
    	for (int i = 1; i < costs.length; i++) {
    		costs[i][0] = costs[i][0] + Math.min(costs[i - 1][1], costs[i - 1][2]);
    		costs[i][1] = costs[i][1] + Math.min(costs[i - 1][0], costs[i - 1][2]);
    		costs[i][2] = costs[i][2] + Math.min(costs[i - 1][0], costs[i - 1][1]);
    	}
    	return Math.min(costs[costs.length - 1][0], Math.min(costs[costs.length - 1][1], costs[costs.length - 1][2]));
    }
}