#include <bits/stdc++.h>
#define INF 1e9
#define EPS 1e-9
#define PI 3.1415926535897932384626433832795
#define MOD 1000000007
#define arr array
#define endl "\n";
#define _min(a) *min_element(a.begin(), a.end());
#define _max(a) *max_element(a.begin(), a.end());
#define _sort(x) sort(x.begin(), x.end())
#define _rsort(x) sort(x.rbegin(), x.rend())
#define _reverse(x) reverse(x.begin(), x.end())
#define _debug(x) cout << #x << " = " << x << endl;
#define debug(x, y) cout << #x " = " << x << " " << #y << " = " << y << endl;
#define _lower_bound(a, x) lower_bound(a.begin(), a.end(), x) - a.begin()
#define _upper_bound(a, x) upper_bound(a.begin(), a.end(), x) - a.begin()
typedef long long ll;
using namespace std;

void solve() {	
	int n, ans; cin >> n;
	vector<ll> a(n), b(n), c(n);
	ll sum1 = 0, sum2 = 0, sum = 0;
	for (int i = 0; i < n; ++i)  {
		cin >> a[i];
		sum += a[i];
		if (i % 2 == 0) {
			b[i] = a[i];
			c[i] = 1;
		}
		else {
			c[i] = a[i];
			b[i] = 1;
		}
		sum1 += abs(a[i] - b[i]);
		sum2 += abs(a[i] - c[i]);
	}
	if (sum1 * 2 <= sum) {
		a = b;
	}
	else {
		a = c;
	}

	for (int i = 0; i < n; ++i) cout << a[i] << " "; cout << endl;
}   

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    int t; cin >> t;
    while(t--) 
        solve();
}
