HDU 4825 Xor Sum 01字典树

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=4825

题意：找出集合中与X异或的最大值

01字典树模板题

代码：

#include 
#include 
#include 
#include 
#define sf scanf
#define pf printf
using namespace std;
const int maxn = 100000 + 5;
typedef long long LL;
int ch[32 * maxn][2];
LL value[32 * maxn];
int node_cnt;

inline void init(){
    node_cnt = 1;
    memset(ch[0],0,sizeof(ch));
}

inline void Insert(LL x){
    int cur = 0;
    for(int i = 32;i >= 0;--i){
        int idx = (x >> i) & 1;
        if(!ch[cur][idx]){
            memset(ch[node_cnt],0,sizeof(ch[node_cnt]));
            ch[cur][idx] = node_cnt;
            value[node_cnt++] = 0;
        }
        cur = ch[cur][idx];
    }
    value[cur] = x;
}

inline LL Query(LL x){
    int cur = 0;
    for(int i = 32;i >= 0;--i){
        int idx = (x >> i) & 1;
        if(ch[cur][idx ^ 1]) cur = ch[cur][idx ^ 1];
        else cur = ch[cur][idx];
    }
    return value[cur];
}

int main(){
    int T,m,temp,n,ca = 0;
    sf("%d",&T);
    while(T--){
        init();
        sf("%d%d",&n,&m);
        for(int i = 0;i < n;++i){
            sf("%d",&temp);Insert(temp);
        }
        pf("Case #%d:\n",++ca);
        for(int i = 0;i < m;++i){
            sf("%d",&temp);pf("%lld\n",Query(temp));
        }
    }
    return 0;
}