【cf842D】Vitya and Strange Lesson（01字典树）

const int N=531000;//3e5<2^19<N
int sw=0;
struct Trie{
	int ch[N*20][2];
	int cnt[N*20];
	int size;
	void Build(int node, int pos){
		if(pos<0)return;
		rep(i,0,2){
			ch[node][i]=++size;
			cnt[size]=0;
			Build(ch[node][i], pos-1);
		}
	}
	void Init(){
		size=0;
		Build(0,19);
	}
	void Insert(int node, int pos, int num){
		if(pos<0)cnt[node]=1;
		if(pos<0) return;
		Insert(ch[node][(num>>pos)&1], pos-1, num);
		cnt[node]=cnt[ch[node][0]]+cnt[ch[node][1]];
	}
	int Query(int node, int pos, int num){
		if(pos<0)
			return num;
		int lson=(sw&(1<<pos))?1:0;
		if(cnt[ch[node][lson]]<(1<<pos)){
			return Query(ch[node][lson], pos-1, num);
		}
		return Query(ch[node][!lson], pos-1,num+(1<<pos));
	}
}trie;
int main() {
	int n,m;
	while(~scanf("%d%d",&n,&m)){
		trie.Init();
		sw=0;
		rep(i,0,n){
			int x;
			scanf("%d",&x);
			trie.Insert(0,19,x);
		}
		while(m--){
			int x;
			scanf("%d",&x);
			sw^=x;
			printf("%d\n",trie.Query(0,19,0));
		}
		puts("");
	}
	return 0;
}

const int N=531000;
int sw=0;
struct Trie{
	int cnt[N*20];
	void Insert(int node, int pos, int num){
		if(pos<0){cnt[node]=1;return;}
		Insert(node<<1|((num>>pos)&1), pos-1, num);
		cnt[node]=cnt[node<<1]+cnt[node<<1|1];
	}
	int Query(int node, int pos, int num){
		if(pos<0) return num;
		int cur=(sw>>pos)&1;
		cur|=node<<1;
		if(cnt[cur]<(1<<pos)) return Query(cur, pos-1, num);
		return Query(cur^1, pos-1,num+(1<<pos));
	}
}trie;
int main() {
	int n,m;
	scanf("%d%d",&n,&m);
	rep(i,0,n){
		int x;
		scanf("%d",&x);
		trie.Insert(1,19,x);
	}
	while(m--){
		int x;
		scanf("%d",&x);
		sw^=x;
		printf("%d\n",trie.Query(1,19,0));
	}
	return 0;
}