leetcode - Climbing Stairs

class Solution {
public:
    int climbStairs(int n) {
        //DP Solution
        int climbNum[100]={0,1,2};
        for( int i = 3; i <= n; i++ ){
            climbNum[i] = climbNum[i-1] + climbNum[i-2];            
        }
        return climbNum[n];
        
        
        
        // Recursion Solution:
        //if(n==1) return 1;
        //if(n==2) return 2;
        //return climbStairs(n-1)+climbStairs(n-2);
        
    }
};