矩形覆盖

public class  {
    public int RectCover(int target) {
		if(target == 1)
            return 1;
        if(target == 2)
            return 2;
        
        int firstCover = 1;
        int secondCover = 2;
        int result = 0;
        
        for(int i = 3; i <= target; i++){
            result = firstCover + secondCover;
            firstCover = secondCover;
            secondCover = result;
        }
        return result;
    }
}