代码随想录day38 | 509. 斐波那契数 70. 爬楼梯 746. 使用最小花费爬楼梯

class Solution {
public:
    int fib(int n) {
        if(n <= 1) return n;
        vector<int> dp(n+1);
        dp[0] = 0;
        dp[1] = 1;
        for(int i = 2; i <= n; i++) {
            dp[i] = dp[i-1] + dp[i-2];
        }
        return dp[n];
    }
};

class Solution {
public:
    int climbStairs(int n) {
        if(n <= 1) return n;
        vector<int> dp(n+1);
        dp[1] = 1;
        dp[2] = 2;
        for(int i = 3; i <= n; i++) {
            dp[i] = dp[i-1] + dp[i-2];
        }  
        return dp[n];
    }
};

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