#include<iostream>
#include<cassert>
using namespace std;
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int T;cin>>T;
	for(;T--;)
	{
		int N;cin>>N;
		if(__builtin_popcount(N)==1)cout<<"-1\n";
		else
		{
			int i=0;
			while(!(N>>i&1))i++;
			i++;
			while(!(N>>i&1))i++;
			cout<<(1<<i)-(N&(1<<i)-1)<<"\n";
		}
	}
}