题目：http://www.nowcoder.com/practice/72a5a919508a4251859fb2cfb987a0e6

C++

1 class Solution { 2 public: 3     int rectCover(int n) { 4         if (n == 1 || n == 2) return n; 5         int a = 1, b = 1; 6         while (n-- >= 2) { 7             a = a + b; 8             b = a - b; 9         }10         return a;11     }12 };