题解 | #最小花费爬楼梯#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param cost int整型一维数组
     * @return int整型
     */
    public int minCostClimbingStairs (int[] cost) {
        // write code here
        if (cost.length == 1) {
            return cost[0];
        }
        if (cost.length == 2) {
            return Math.max(cost[0], cost[1]);
        }
        if (cost.length == 3) {
            return Math.min(cost[0] + cost[2], cost[1]);
        }
        int[] dp = new int[cost.length + 1];
        dp[0] = 0;
        dp[1] = cost[0];
        dp[2] = Math.min(cost[0], cost[1]);
        dp[3] = Math.min(cost[0] + cost[2], cost[1]);
        for (int i = 4; i < dp.length; i++) {
            dp[i] = Math.min(dp[i - 2] + cost[i - 2], dp[i - 1] + cost[i - 1]);
        }
        return dp[dp.length - 1];
    }
}