牛客_跳台阶

跳台阶
https://www.nowcoder.com/practice/8c82a5b80378478f9484d87d1c5f12a4

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param number int整型 
     * @return int整型
     */
    public int jumpFloor (int number) {
        return solution1(number);
        // return solution2(number);
    }

    private int solution1(int number){
        if(number == 0){
            return 1;
        }
        if(number == 1){
            return 1;
        }

        return solution1(number-1)+solution1(number-2);
    }

    private int solution2(int number){
        if(number == 0){
            return 1;
        }
        if(number == 1){
            return 1;
        }

        int f1 = 1;
        int f2 = 1;
        int result = 0;
        for(int i=2; i<=number; i++){
            result = f1+f2;
            f1 = f2;
            f2 = result;
        }

        return result;
    }
}