JZ10、矩形覆盖

递推公式： f(n) = f(n -1) + f(n-2)

public class Solution {
    public int RectCover(int target) {
        if(target <= 1)
             return target;
        int a = 1,b = 2, temp = 2;
        for(int i = 2; i < target; i++){
            temp = b;
            b += a;
            a = temp;
        }        
        return b;
    }
}