java 爬楼梯算法实现

java 爬楼梯算法实现

方法一：

public class Run {public static void main(String[] args) {//startUp()传入楼梯数，因为测试，我输入了个5System.out.println(startUp(5));}public static int startUp(int n){if(n ==3)return 4;if(n <3)return n;return startUp(n-1) + startUp(n-2) + startUp(n-3);}}

方法二：

    static int getCount(int level){        switch(level){            case 1:                return 1;            case 2:                return 2;            case 3:                return 4;        }        int count = 0;        for (int i = 0; i < level; i++) {            count += getCount(i);        }        return count;    }