10_____ rectangular footprint

Subject description:

We can use a small rectangle 2 * 1 sideways or vertically to cover a larger rectangle. Will the small rectangle of n 2 * 1 coverage without overlap a large rectangle 2 * n, a total of how many ways?

public  class Solution {
 // similar Fibonacci law of Number of
 // F (n-) = F (n--. 1) + F (n-2-); 
    public  int RectCover ( int target) {
         IF (target ==. 1 ) {
             return . 1 ; 
        } 
        
        IF (target == 2 ) {
             return 2 ; 
        } 
        
        int prepreNum =. 1 ;
         int preNum = 2 ;
         int RES = 0 ;
         for ( int I =. 3; I <= target; I ++ ) { 
            RES = prepreNum +penalty; 
            prepreNum = penalty; 
            Prenés = a; 
        } 
        Return res; 
    } 
}