字典树模板

#include<iostream>
#include<cstdio>
using namespace std;

struct Trie{
    struct node{
        long long val;
        int num;
        node *ch[2];
        node()
        {
            ch[0] = ch[1] = NULL;
        }
    }*rt;

    void init()
    {
        rt = new node();
    }

    void insert(long long x,int y)
    {
        node *cur = rt;
        for(int i = 32; i >=0; i--){
//            cout<<(x>>i&1)<<endl;
            if( cur->ch[x>>i&1] == NULL) cur->ch[x>>i&1] = new node();
            cur = cur->ch[x>>i&1];
        }
        cur->val = x;
        cur->num = y;
    }

    int query(long long x)
    {
        node *cur = rt;
        for(int i = 32; i >= 0; i--){
            int tb = x>>i&1;
            if(cur->ch[tb^1] != NULL) cur = cur->ch[tb^1];
            else cur = cur->ch[tb];
        }
        return cur->val;
    }
};

int main()
{
    int t;
    scanf("%d",&t);
    int tt = 1;
    while(t--){

        int n,m;
        scanf("%d%d",&n,&m);
        Trie T;
        T.init();
        for(int i = 1; i <= n; i++){
            long long x;
            scanf("%lld",&x);
            T.insert(x,i);
        }
        printf("Case #%d:\n",tt++);
        for(int i = 1; i <= m; i++){
            int x;
            scanf("%d",&x);
            printf("%d\n",T.query(x));
        }

    }
    return 0;
}