Author has gone out of the stories about Vasiliy, so here is just a formal task description.

You are given q queries and a multiset A, initially containing only integer 0. There are three types of queries:

  1. "+ x" — add integer x to multiset A.
  2. "- x" — erase one occurrence of integer x from multiset A. It's guaranteed that at least one x is present in the multiset A before this query.
  3. "? x" — you are given integer x and need to compute the value <image>, i.e. the maximum value of bitwise exclusive OR (also know as XOR) of integer x and some integer y from the multiset A.



Multiset is a set, where equal elements are allowed.

Input

The first line of the input contains a single integer q (1 ≤ q ≤ 200 000) — the number of queries Vasiliy has to perform.

Each of the following q lines of the input contains one of three characters '+', '-' or '?' and an integer xi (1 ≤ xi ≤ 109). It's guaranteed that there is at least one query of the third type.

Note, that the integer 0 will always be present in the set A.

Output

For each query of the type '?' print one integer — the maximum value of bitwise exclusive OR (XOR) of integer xi and some integer from the multiset A.

Example

Input

10
+ 8
+ 9
+ 11
+ 6
+ 1
? 3
- 8
? 3
? 8
? 11


Output

11
10
14
13

Note

After first five operations multiset A contains integers 0, 8, 9, 11, 6 and 1.

The answer for the sixth query is integer <image> — maximum among integers <image>, <image>, <image>, <image> and <image>.
//package round367;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;

public class D {
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	void solve()
	{
		int Q = ni();
		int[][] qs = new int[Q][];
		int[] vs = new int[Q+1];
		int p = 0;
		vs[p++] = 0;
		for(int i = 0;i < Q;i++){
			char t = nc();
			int v = ni();
			qs[i] = new int[]{t, v};
			if(t == '+'){
				vs[p++] = v;
			}
		}
		int[] imap = shrinkX(vs);
		int m = imap.length;
		int[] ft = new int[m+3];
		addFenwick(ft, 0, 1);
		for(int[] q : qs){
			if(q[0] == '+'){
				int ind = Arrays.binarySearch(imap, q[1]);
				addFenwick(ft, ind, 1);
			}else if(q[0] == '-'){
				int ind = Arrays.binarySearch(imap, q[1]);
				addFenwick(ft, ind, -1);
			}else{
				int x = q[1];
				int v = 0;
				int l = 0, r = m;
				for(int d = 30;d >= 0;d--){
					int nv = v|1<<d;
					int ind = Arrays.binarySearch(imap, nv);
					if(ind < 0)ind = -ind-1;
					if(x<<~d<0){
						int count = sumFenwick(ft, ind-1) - sumFenwick(ft, l-1);
						if(count > 0){
							r = ind;
						}else{
							l = ind;
							v = nv;
						}
					}else{
						int count = sumFenwick(ft, r-1) - sumFenwick(ft, ind-1);
						if(count > 0){
							l = ind;
							v = nv;
						}else{
							r = ind;
						}
					}
				}
				out.println(v^x);
			}
		}
	}
	
	public static int sumFenwick(int[] ft, int i) {
		int sum = 0;
		for (i++; i > 0; i -= i & -i)
			sum += ft[i];
		return sum;
	}

	public static void addFenwick(int[] ft, int i, int v) {
		if (v == 0 || i < 0)
			return;
		int n = ft.length;
		for (i++; i < n; i += i & -i)
			ft[i] += v;
	}

	public static int findGFenwick(int[] ft, int v) {
		int i = 0;
		int n = ft.length;
		for (int b = Integer.highestOneBit(n); b != 0 && i < n; b >>= 1) {
			if (i + b < n) {
				int t = i + b;
				if (v >= ft[t]) {
					i = t;
					v -= ft[t];
				}
			}
		}
		return v != 0 ? -(i + 1) : i - 1;
	}

	public static int valFenwick(int[] ft, int i) {
		return sumFenwick(ft, i) - sumFenwick(ft, i - 1);
	}

	public static int[] restoreFenwick(int[] ft) {
		int n = ft.length - 1;
		int[] ret = new int[n];
		for (int i = 0; i < n; i++)
			ret[i] = sumFenwick(ft, i);
		for (int i = n - 1; i >= 1; i--)
			ret[i] -= ret[i - 1];
		return ret;
	}

	public static int before(int[] ft, int x) {
		int u = sumFenwick(ft, x - 1);
		if (u == 0)
			return -1;
		return findGFenwick(ft, u - 1) + 1;
	}

	public static int after(int[] ft, int x) {
		int u = sumFenwick(ft, x);
		int f = findGFenwick(ft, u);
		if (f + 1 >= ft.length - 1)
			return -1;
		return f + 1;
	}

	public static int[] buildFenwick(int[] a) {
		int n = a.length;
		int[] ft = new int[n + 1];
		System.arraycopy(a, 0, ft, 1, n);
		for (int k = 2, h = 1; k <= n; k *= 2, h *= 2) {
			for (int i = k; i <= n; i += k) {
				ft[i] += ft[i - h];
			}
		}
		return ft;
	}

	public static int[] buildFenwick(int n, int v) {
		int[] ft = new int[n + 1];
		Arrays.fill(ft, 1, n + 1, v);
		for (int k = 2, h = 1; k <= n; k *= 2, h *= 2) {
			for (int i = k; i <= n; i += k) {
				ft[i] += ft[i - h];
			}
		}
		return ft;
	}

	
	public static int[] shrinkX(int[] a) {
		int n = a.length;
		long[] b = new long[n];
		for (int i = 0; i < n; i++)
			b[i] = (long) a[i] << 32 | i;
		Arrays.sort(b);
		int[] ret = new int[n];
		int p = 0;
		ret[0] = (int) (b[0] >> 32);
		for (int i = 0; i < n; i++) {
			if (i > 0 && (b[i] ^ b[i - 1]) >> 32 != 0) {
				p++;
				ret[p] = (int) (b[i] >> 32);
			}
			a[(int) b[i]] = p;
		}
		return Arrays.copyOf(ret, p + 1);
	}

	
	public static int[] radixSort(int[] f)
	{
		int[] to = new int[f.length];
		{
			int[] b = new int[65537];
			for(int i = 0;i < f.length;i++)b[1+(f[i]&0xffff)]++;
			for(int i = 1;i <= 65536;i++)b[i]+=b[i-1];
			for(int i = 0;i < f.length;i++)to[b[f[i]&0xffff]++] = f[i];
			int[] d = f; f = to;to = d;
		}
		{
			int[] b = new int[65537];
			for(int i = 0;i < f.length;i++)b[1+(f[i]>>>16)]++;
			for(int i = 1;i <= 65536;i++)b[i]+=b[i-1];
			for(int i = 0;i < f.length;i++)to[b[f[i]>>>16]++] = f[i];
			int[] d = f; f = to;to = d;
		}
		return f;
	}

	void run() throws Exception
	{
		is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new PrintWriter(System.out);
		
		long s = System.currentTimeMillis();
		solve();
		out.flush();
		tr(System.currentTimeMillis()-s+"ms");
	}
	
	public static void main(String[] args) throws Exception { new D().run(); }
	
	private byte[] inbuf = new byte[1024];
	private int lenbuf = 0, ptrbuf = 0;
	
	private int readByte()
	{
		if(lenbuf == -1)throw new InputMismatchException();
		if(ptrbuf >= lenbuf){
			ptrbuf = 0;
			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
			if(lenbuf <= 0)return -1;
		}
		return inbuf[ptrbuf++];
	}
	
	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
	
	private double nd() { return Double.parseDouble(ns()); }
	private char nc() { return (char)skip(); }
	
	private String ns()
	{
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	
	private char[] ns(int n)
	{
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while(p < n && !(isSpaceChar(b))){
			buf[p++] = (char)b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}
	
	private char[][] nm(int n, int m)
	{
		char[][] map = new char[n][];
		for(int i = 0;i < n;i++)map[i] = ns(m);
		return map;
	}
	
	private int[] na(int n)
	{
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}
	
	private int ni()
	{
		int num = 0, b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private long nl()
	{
		long num = 0;
		int b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private boolean oj = System.getProperty("ONLINE_JUDGE") != null;
	private void tr(Object... o) { if(!oj)System.out.println(Arrays.deepToString(o)); }
}
