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?

 

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　　这题其实就是斐波那契数列来的。

#include 
       
        using namespace std;class Solution {public:    int climbStairs(int n) {        if(n<2) return 1;        int l=1,r=1,tmp;        for(int i=2;i<=n;i++){            tmp=l+r;            l=r;            r=tmp;        }        return r;    }};int main(){    Solution sol;    for(int i =0;i<9;i++)    cout<
        
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