#include <iostream>
#include <vector>
#include <bitset>
#include <algorithm>
#include <cmath>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vmi = vector<mint>;
using vvmi = vector<vmi>;
using vvvmi = vector<vvmi>;
#define all(a) (a).begin(), (a).end()
#define rep2(i, m, n) for (int i = (m); i < (n); ++i)
#define rep(i, n) rep2(i, 0, n)
#define drep2(i, m, n) for (int i = (m)-1; i >= (n); --i)
#define drep(i, n) drep2(i, n, 0)


int main(){
    int t; cin >> t;
    while(t--){
        int n; cin >> n;
        bitset<32> bs(n);
        if(bs.count() == 1){
            cout << -1 << endl;
            continue;
        }
        bool f = false;
        rep(i, 31){
            if(bs[i] && bs[i+1]){
                bitset<32> ans(0);
                rep(j, 32)ans[j] = (j == i) ? 1 : 0;
                cout << ans.to_ulong() << endl;
                f = true;
                break;
            }
            if(f)break;
        }
        if(f)continue;
        int c = 0;
        rep(i, 32){
            if(bs[i]){
                c++;
            }
            if(c == 2){
                bitset<32> ans(0);
                ans[i+1] = 1;
                rep2(j, i+2, 32)ans[j] = bs[j];
                cout << ans.to_ulong() - n << endl;
                break;
            }
        }
    }

    return 0;
}