#include <bits/stdc++.h>
using namespace std;

template <typename T, typename F>
class SegmentTree {
    F op;
    T e;
    int size;
    vector<T> data;

    void init(int n) {
        int log = 1;
        while (n > (1 << log)) ++log;
        size = 1 << log;

        data.assign(size << 1, e);
    }

    void update(int k) {
        k >>= 1;
        while (k > 0) {
            data[k] = op(data[k << 1], data[(k << 1) + 1]);
            k >>= 1;
        }
    }

  public:
    SegmentTree(int n, F op_, T e_) : op(op_), e(e_) {
        init(n);
    }

    SegmentTree(const vector<T> &v, F op_, T e_) : op(op_), e(e_) {
        int n = v.size();
        init(n);

        for (int i = 0; i < n; i++) {
            data[i + size] = v[i];
        }

        for (int i = size - 1; i > 0; --i) {
            data[i] = op(data[i << 1], data[(i << 1) + 1]);
        }
    }

    void set(int k, T v) {
        k += size;
        data[k] = v;

        update(k);
    }

    void add(int k, T v) {
        k += size;
        data[k] += v;

        update(k);
    }

    T get_all() {
        return data[1];
    }

    T get_range(int l, int r) {
        T result_l = e, result_r = e;
        l += size;
        r += size;

        while (l < r) {
            if (l & 1) {
                result_l = op(result_l, data[l++]);
            }
            if (r & 1) {
                result_r = op(data[--r], result_r);
            }
            l >>= 1;
            r >>= 1;
        }

        return op(result_l, result_r);
    }

    T operator[](int k) {
        return data[k + size];
    }
};

void solve() {
    int q;
    cin >> q;
    vector<pair<int, int>> query;
    query.reserve(q);
    map<int, int> mp;
    int n = 0;

    for (int i = 0; i < q; i++) {
        int t, x = 0;
        cin >> t;
        if (t == 1 || t == 2) {
            cin >> x;
            if (mp.find(x) == mp.end()) {
                mp[x] = n++;
            }
        }
        query.emplace_back(t, x);
    }

    auto f = [](int x, int y) -> int {
        return x & y;
    };

    int e = (1 << 30) - 1;
    SegmentTree<int, decltype(f)> seg(n, f, e);
    set<int> s;

    for (auto &[t, x]: query) {
        if (t == 1) {
            int i = mp[x];
            seg.set(i, x);
            s.insert(x);
        } else if (t == 2) {
            int i = mp[x];
            seg.set(i, e);
            s.erase(x);
        } else {
            if (s.size() == 0) {
                cout << -1 << '\n';
            } else {
                cout << seg.get_all() << '\n';
            }
        }
    }
}

int main() {
    int q = 1;
    // cin >> q;
    while (q--) {
        solve();
    }
}