Leetcode 70 Climbing Stairs

Leetcode 70 Climbing Stairs

//fibonacci sequence excluding leading one#include <vector>#include <math.h>using namespace std;class Solution {public:    int climbStairs(int n) {        if(n <= 0)            return 0;        if(n == 1)            return 1;        vector<int> sequence;        sequence.push_back(1);        sequence.push_back(1);        for(int i = 2; i < n + 1;i++)        {            sequence.push_back(sequence[i-1] + sequence[i-2]);        }        return sequence[sequence.size() - 1];    }    int climbStairs2(int n) {        const double s = sqrt(5);        return floor((pow((1+s)/2,n+1)+pow((1-s)/2,n+1))/s + 0.5);    }//to learn 什么解法……};