Leetcode 746. Min Cost Climbing Stairs 最小成本爬楼梯 (动态规划)

Input: cost = [10, 15, 20]
Output: 15
Explanation: 从第一阶出发，一次走两步

Input: cost = [1, 100, 1, 1, 1, 100, 1, 1, 100, 1]
Output: 6
Explanation: 从地面出发，走两步，走两步，走两步，走一步，走两步，走一步。

class Solution {
public:
    int minCostClimbingStairs(vector<int>& cost) {
        if(cost.size()==0){
            return 0;
        }
        if(cost.size()==1){
            return cost[0];
        }
        if(cost.size()==2){
            return std::min(cost[0],cost[1]);
        }
        int step[1024];
        step[0] = 0;
        step[1] = 0;
        for(int i=2;i<=cost.size();i++){
            step[i] = std::min(step[i-1]+cost[i-1],step[i-2]+cost[i-2]);
        }
        return step[cost.size()];
    }
};