- Question:
You are climbing a stair case. It takes n steps to reach to the top.
Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?
Note: Given n will be a positive integer.
- Analysis:
这是一个爬梯子的问题,要到达第n级阶梯则只能是从n-1级阶梯一步跨上来或者是从n-2级阶梯一次跨两步上来,由此很容易可以得到状态转移方程为:
S[n] = S[n-1] + S[n-2]。代码如下所示:
- Code:
class Solution { public: int climbStairs(int n) { int result = 0; int temp[n+1] = {1}; temp[1] = 1; for (int i=2;i<=n;i++) { temp[i] = temp[i-1] + temp[i-2]; } return temp[n]; } };