The binomial coefficient C(n, k) has been extensively studied for its importance in combinatorics. Binomial coefficients can be recursively defined as follows:

C(n, 0) = C(n, n) = 1 for all n > 0;
C(n, k) = C(n − 1, k − 1) + C(n − 1, k) for all 0 < k < n.

Given n and k, you are to determine the parity of C(n, k).

The input contains multiple test cases. Each test case consists of a pair of integers n and k (0 ≤ k ≤ n < 2³¹, n > 0) on a separate line.
End of file (EOF) indicates the end of input.

For each test case, output one line containing either a “0” or a “1”, which is the remainder of C(n, k) divided by two.

组合数学