//There are a row of n houses, each house can be painted with one of the three colors: red, blue or green. //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 3 cost matrix. For example, //costs[0][0] is the cost of painting house 0 with color red; costs[1][2] is the cost of painting house 1 //with color green, and so on... Find the minimum cost to paint all houses. //Note: //All costs are positive integers. class PaintHouse { public int minCost(int[][] costs) { if(costs == null || costs.length == 0) { return 0; } for(int i = 1; i < costs.length; i++) { costs[i][0] += Math.min(costs[i - 1][1], costs[i - 1][2]); costs[i][1] += Math.min(costs[i - 1][0], costs[i - 1][2]); costs[i][2] += Math.min(costs[i - 1][0], costs[i - 1][1]); } return Math.min(Math.min(costs[costs.length - 1][0], costs[costs.length - 1][1]), costs[costs.length - 1][2]); } }