Codeforces 909F and-permutations

Source:s o u r C e:source:codeforces Round #455 (Div. 2)
Problem:p R o b l e m:problem: Gives an n (1≤n≤105) n (1≤n≤10 5) n (1≤n≤10^5), constructs a full permutation of two n, the first sequence pi≠i and pi   P I≠i and P I pi≠i and pi & i = 0 i = 0 i = 0, second sequence pi≠i and pi p i≠i and P I pi≠i and pi & i≠0 i≠ 0 i≠0.
IDEA:I d e A:idea:
For the first sequence, note that 2k+i+2k−i−1=2k+1−1 2 k + i + 2 k−i−1 = 2 K + 1−1 2^k+i + 2^k-i-1 = 2^{k+1}-1, So (2k+i) (2 k + i) (2^k+ i) & (2k−i−1) =0 (2 k−i−1) = 0 (2^k-i-1) = 0, cannot be constructed when n is odd.
For the second sequence, note that there is a loop corresponding to the same highest bit, then when N is a power of 2 can not be constructed, and because of the existence of 1, less than 8 of the case of special treatment.