10.矩形覆盖

public class Solution {
    public int RectCover(int target) {
        if(target<=0){
            return 0;
        }
        if(target==1 || target==2){
            return target;
        }
        int res=2;
        int pre=1;
        int tmp=0;
        for(int i=3;i<=target;i++){
            tmp=res;
            res=res+pre;
            pre=tmp;
        }
        return res;
    }
}

public class Solution {
    public int RectCover(int target) {
        if(target<=0){
            return 0;
        }
        if(target==1 || target==2){
            return target;
        }
        
        return RectCover(target-1)+RectCover(target-2);
    }
}