class Solution {
public:
    int jumpFloor(int number) {
        if(number <= 2){
            return number;
        }
        
        int n_2 = 1;
        int n_1 = 2;
        int res;
        
        for(int i=3; i<=number; i++){
            res = n_1 + n_2;
            n_2 = n_1;
            n_1 = res;
        }
        return res;
    }
};