#include <bits/stdc++.h>
#define int long long
#define FOR(g,z,t) for(int g=z; g<=t; ++g)
using namespace std;
const int N = (3*1e5+1)*32;
int n;
int child[N][2],cnt=0,num[N];

int Getbit(int val, int pos) {
 return 1 & (val >> (pos-1));
}

void ADD(int x) {
    int node =0;
    for(int i=31; i>=1; --i) {
        int k = Getbit(x,i);
        if (!child[node][k]) child[node][k]=++cnt;
        ++num[child[node][k]];
        node=child[node][k];
    }
}

int Query(int k) {
    int ans = 0;
    int node = 0;
    for(int i=31; i>=1; --i) {
        if (k <= num[child[node][0]]) node = child[node][0];
        else {
            k -= num[child[node][0]];
            ans += 1 << (i-1);
            node = child[node][1];
        }
    }
    return ans;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    freopen("RANDNUM.INP","r",stdin);
    cin >> n;
    while (n--) {
        int type,val;
        cin >> type >> val;
        if (type == 1) {
            ADD(val);
        }
        else  {
            cout << Query(val) << endl;
        }
    }
    return 0;
}