Source: Climbing Stairs - LeetCode

状态转移方程

题解

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