LeetCode:Climbing Stairs(DP)

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?

class Solution {
public:
    int climbStairs(int n) {
        
        
        int *step_count=new int[n+1];
        step_count[1]=1;
        step_count[2]=2;
        
        //动归方程
        for(int i=3;i<n+1;i++)
            step_count[i]=step_count[i-1]+step_count[i-2];
        return step_count[n];
    }
};