D. Vitya and Strange Lesson Codeforces Round #430 (Div. 2)

http://codeforces.com/contest/842/problem/D

树 二进制(路径，每个节点代表一位)

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <time.h>
#include <string>
#include <set>
#include <map>
#include <list>
#include <stack>
#include <queue>
#include <vector>
#include <bitset>
#include <ext/rope>
#include <algorithm>
#include <iostream>
using namespace std;
#define ll long long
#define minv 1e-6
#define inf 1e9
#define pi 3.1415926536
#define E  2.7182818284
const ll mod=1e9+7;//998244353
const int maxn=1e5+10;

bool tr[524288<<2]={0};//19+2
int f[21];
int w=19;

int main()
{
    int n,m,a,b,i,j,k,value;
    scanf("%d%d",&n,&m);
    while (n--)
    {
        scanf("%d",&a);
        b=a;
        for (i=w;i>=1;i--)
        {

            f[i]=a & 1;
            a>>=1;
        }
        j=1;
        for (i=1;i<=w;i++)
        {
            j<<=1;
            if (f[i]==1)
                j++;
        }
        tr[j]=1;
    }

    for (i=(1<<w)-1;i>=1;i--)
        tr[i]=tr[i<<1]&tr[i<<1|1];

    b=0;
    while (m--)
    {
        scanf("%d",&a);
        b=a^b;

        a=b;
        for (i=w;i>=1;i--)
        {
            f[i]=a & 1;
            a>>=1;
        }
        j=1;
        k=1<<(w-1);
        value=0;
        for (i=1;i<=w;i++)
        {
            j<<=1;
            if (!tr[j+f[i]])
            {
                j+=f[i];
            }
            else
            {
                j+=(f[i] ^ 1);
                value+=k;
            }
            k>>=1;
        }
        printf("%d
",value);
    }
    return 0;
}