#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define rd_init() char*rp=({char*mmap();mmap(0l,1l<<25,1,2,0,0ll);})
#define rd() ({int _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;})
#define WTHI(v) {unsigned _z=v,_n=0;long _d=0;while(++_n,_d=_d<<8|0x30|_z%10,_z/=10);*(long*)wp=_d;wp+=_n;}
#define WTLO(v) {unsigned _z=v,_n=8;long _d=0;while(_d=_d<<8|0x30|_z%10,_z/=10,--_n);*(long*)wp=_d;wp+=8;}
#define wt(v) if(v>=100000000){WTHI(v/100000000);WTLO(v);}else{WTHI(v);}
#define rep(v,e) for(typeof(e)v=0;v<e;++v)
#define rrep(v,e) for(typeof(e)v=e;v--;)
#define repeat(e) for(typeof(e)_=e;_--;)

char wbuf[1<<25];

#define HASH_N 800011
unsigned hash[HASH_N];

int hash_add(unsigned x){
	int h=x%HASH_N;
	while(1){
		if(hash[h]==0){
			hash[h]=x;
			return h;
		}
		if(hash[h]==x){
			return h;
		}
		h=h+1;
		h=h>=HASH_N?0:h;
	}
}

char c[HASH_N];
int a[31];

int main(){
	rd_init();
	int q=rd();
	char*wp=wbuf;
	repeat(q){
		int t=*rp; rp+=2;
		if(t=='1'){
			unsigned x=rd();
			int h=hash_add(x+1);
			if(!c[h]){
				c[h]=1;
				rep(i,31){
					a[i]+=~x&1;
					x>>=1;
				}
			}
		}
		if(t=='2'){
			unsigned x=rd();
			int h=hash_add(x+1);
			if(c[h]){
				c[h]=0;
				rep(i,31){
					a[i]-=~x&1;
					x>>=1;
				}
			}
		}
		if(t=='3'){
			unsigned v=0;
			rrep(i,31){
				v=v<<1|!a[i];
			}
			if(v&1<<30){
				*wp++='-';
				*wp++='1';
			}else{
				wt(v);
			}
			*wp++='\n';
		}
	}
	write(1,wbuf,wp-wbuf);
	_exit(0);
}