CodeForces 909F AND-permutations

S o u r c e : Codeforces Round #455 (Div. 2)
P r o b l e m : 给一个 N ( 1 N 10 5 ) ,构造两个n的全排列,第一个序列 p i i p i & i = 0 ,第二个序列 p i i p i & i 0
I d e a :
对于第一种序列,注意到 2 k + i + 2 k i 1 = 2 k + 1 1 ,所以 ( 2 k + i ) & ( 2 k i 1 ) = 0 ,当n是奇数时无法构造。
对于第二种序列,注意到有相同最高位的循环对应即可,那么当n是2的幂次时无法构造,并且由于1的存在,对小于8的情况特殊处理。
C o d e :

#include<bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define pb push_back
#define CLR(A, X) memset(A, X, sizeof(A))
#define bitcount(X) __builtin_popcountll(X)
typedef long long LL;
typedef pair<int, int> PII;
typedef pair<char, int> PCI;
const double eps = 1e-10;
const double PI = acos(-1.0);
const auto INF = 0x3f3f3f3f;
const int MOD = 1e9+7;
int dcmp(double x) { if(fabs(x) < eps) return 0; return x<0?-1:1; }

const int MAXN = 1e5+10;

int vis[MAXN];

int main() {
    int n, y = 1;
    scanf("%d", &n);
    while((y<<1) <= n) y <<= 1;

    if(n & 1) puts("NO");
    else {
        puts("YES");
        int t = y;
        for(int i = n; i >= 1; i--) {
            if(t > i) t >>= 1;
            if(!vis[i]) {
                int x = t-(i-t)-1;
                vis[i] = x;
                vis[x] = i;
            }
        }
        for(int i = 1; i <= n; i++) {
            printf("%d ", vis[i]);
        }
        puts("");
    }

    if(n==y || n<6) puts("NO");
    else {
        puts("YES");
        if(n == 6) puts("3 6 2 5 1 4");
        else {
            printf("7 3 6 5 1 2 4 ");
            for(int i = 8; i <= n; ) {
                int j = min(i<<1, n+1);
                for(int k = i; k < j-1; k++) printf("%d ", k+1);
                printf("%d ", i);
                i = j;
            }
        }
    }
    return 0;
}

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转载自blog.csdn.net/qq_32506797/article/details/79369862