CF D. Ehab and the Expected XOR Problem 贪心+位运算

code:

#include <bits/stdc++.h>
#define N 1000000
#define setIO(s) freopen(s".in","r",stdin)
using namespace std;
int vis[N],b[N];
void solve()
{
    int n,m,i,j,cur=1,cnt=0;
    memset(vis,0,sizeof(vis));
    scanf("%d%d",&n,&m);
    vis[m]=1;
    for(i=1;i<=(1<<n);++i)
    {
        while(vis[cur]) ++cur;
        if((cur^b[cnt-1]) >= (1<<n)) break;
        b[++cnt]=cur;
        vis[cur^m]=1;
        ++cur;
    }
    printf("%d\n",cnt);
    for(i=0;i<cnt;++i) printf("%d ",b[i]^b[i+1]);
}
int main()
{
    int i,j,T;
    // setIO("input");
    solve();
    return 0;
}

原文地址：https://www.cnblogs.com/guangheli/p/11641816.html