P10975 Mondriaan's Dream / Mondriaan's Dream

The famous Dutch painter Piet Mondriaan was fascinated by squares and rectangles. One night, after finishing his “Toilet Series” paintings (he had to paint on toilet paper because he had run out of canvas), he dreamed of filling a large rectangle in different ways using small rectangles of width $2$ and height $1$.  As an expert in this area, he immediately realized that a computer was needed to compute the number of different ways to fill the large rectangle. Please help him, so that his dream does not turn into a nightmare.

The input contains multiple test cases. Each test case consists of two integers: the height $h$ and width $w$ of the large rectangle. The input ends when $h = w = 0$. Otherwise, $1 \leq h, w \leq 11$.

For each test case, output the number of different ways to tile the given large rectangle using small rectangles of size $2 \times 1$. Assume that the given large rectangle is oriented, meaning that symmetric tilings should be counted multiple times.

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