Score : 800 points
You are given integers N,\ A and B. Determine if there exists a permutation (P_0,\ P_1,\ ...\ P_{2^N-1}) of (0,\ 1,\ ...\ 2^N-1) that satisfies all of the following conditions, and create one such permutation if it exists.
Input is given from Standard Input in the following format:
N A B
If there is no permutation that satisfies the conditions, print NO
.
If there is such a permutation, print YES
in the first line.
Then, print (P_0,\ P_1,\ ...\ P_{2^N-1}) in the second line, with spaces in between.
If there are multiple solutions, any of them is accepted.
2 1 3
YES 1 0 2 3
The binary representation of P=(1,0,2,3) is (01,00,10,11), where any two adjacent elements differ by exactly one bit.
3 2 1
NO