#include <bits/stdc++.h>
#define N 2009
using namespace std;
int a[N][N], b[N][N];
int n, m;

void solve() {
	cin >> n >> m;
	int cnt1 = 0, cnt2 = 0;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			a[i][j] = (!!(i % 4) == !!(j % 4));
			b[i][j] = ((i + j) % 4 != 3);
			if (a[i][j])
				cnt1++;
			if (b[i][j])
				cnt2++;
		}
	}
	cout << max(cnt1, cnt2) << endl;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			int tmp = 0;
			if (cnt1 > cnt2)
				tmp = a[i][j];
			else
				tmp = b[i][j];
			putchar(tmp + '0');
		}
		putchar('\n');
	}
}

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