0746-min-cost-climbing-stairs.java

class Solution {

    public int minCostClimbingStairs(int[] cost) {
        int[] res = new int[cost.length + 1];
        res[cost.length] = 0;
        res[cost.length - 1] = cost[cost.length - 1];

        for (int i = cost.length - 2; i >= 0; i--) {
            res[i] =
                (res[i + 1] < res[i + 2])
                    ? res[i + 1] + cost[i]
                    : res[i + 2] + cost[i];
        }

        return Math.min(res[0], res[1]);
    }
}