矩形覆盖

public class Solution {
public int RectCover(int target) {
if(target  <= 1){
return 1;
}
if(target*2 == 2){
return 1;
}else if(target*2 == 4){
return 2;
}else{
return RectCover((target-1))+RectCover(target-2);
}
}
}