LeetCode:Climbing Stairs

 1 class Solution {
 2 public:
 3     int climbStairs(int n) {
 4         
 5         
 6         int *step_count=new int[n+1];
 7         step_count[1]=1;
 8         step_count[2]=2;
 9         
10         //动归方程
11         for(int i=3;i<n+1;i++)
12             step_count[i]=step_count[i-1]+step_count[i-2];
13         return step_count[n];
14     }
15 };