#include <stdio.h>
#include <string.h>
#include <assert.h>

#include <queue>
#include <algorithm>

#define LOG(FMT...) fprintf(stderr, FMT)

#define eb emplace_back
#define em emplace

using namespace std;

typedef long long LL;
constexpr int N = 1024;
constexpr int rem[4] = {3, 1, 2, 0};
constexpr int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0};

char gr[N][N];
int a[N][N];
int n, m;

bool chk(int bx, int by) {
	static bool vis[N][N];
	static int q[2 * N * N], hh, tt;
	for (int i = 0; i < n; ++i) {
		memset(vis[i], 0, m);
	}
	int sx = -1, sy = -1;
	for (int x = 0; x < n; ++x) {
		for (int y = 0; y < m; ++y) {
			if (gr[bx + x][by + x] == '1') {
				sx = x, sy = y;
			}
		}
	}
	vis[sx][sy] = true;
	q[0] = sx, q[1] = sy, hh = 0, tt = 2;
	while (hh != tt) {
		int x = q[hh++], y = q[hh++];
		for (int d = 0; d < 4; ++d) {
			int tx = x + dx[d], ty = y + dy[d];
			if (tx < 0 || ty < 0 || tx >= n || ty >= m || gr[bx + tx][by + ty] != '1' || vis[tx][ty]) {
				continue;
			}
			vis[tx][ty] = true;
			q[tt++] = tx, q[tt++] = ty;
		}
	}
	for (int x = 0; x < n; ++x) {
		for (int y = 0; y < m; ++y) {
			if (gr[bx + x][by + y] == '1' && !vis[x][y]) {
				return true;
			}
		}
	}
	return false;
}

int main() {
	n = 1020, m = 1020;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < m; ++j) {
			gr[i + 1][j + 1] = "01"[(j & 3) != rem[i & 3]];
			a[i + 1][j + 1] = (gr[i + 1][j + 1] == '1') + a[i + 1][j] + a[i][j + 1] - a[i][j];
		}
	}
	/* for (int x = 0; x < 32; ++x) {
		for (int y = 0; y < 32; ++y) {
			putchar(gr[x][y]);
		}
		puts("");
	}
	exit(0); */
	int task;
	for (scanf("%d", &task); task--; ) {
		scanf("%d%d", &n, &m);
		if (n < 4 && m < 4) {
			printf("%d\n", n * m);
			for (int i = 0; i < n; ++i) {
				for (int j = 0; j < m; ++j) {
					putchar('1');
				}
				puts("");
			}
		} else if (n == 3) {
			printf("%d\n", n * (m - m / 4) - (m % 4 >= 2));
			for (int i = 0; i < n; ++i) {
				for (int j = 0; j < m; ++j) {
					putchar("01"[(j & 3) != rem[i & 1]]);
				}
				puts("");
			}
		} else if (m == 3) {
			printf("%d\n", m * (n - n / 4) - (n % 4 >= 2));
			for (int i = 0; i < n; ++i) {
				for (int j = 0; j < m; ++j) {
					putchar("01"[(i & 3) != rem[j & 1]]);
				}
				puts("");
			}
		} else {
			int res = 0, rx = -1, ry = -1;
			for (int x = 0; x < 4; ++x) {
				for (int y = 0; y < 4; ++y) {
					if (chk(x + 1, y + 1)) {
						continue;
					}
					int v = a[x + n][y + m] - a[x + n][y] - a[x][y + m] + a[x][y];
					if (v <= res) {
						continue;
					}
					res = v, rx = x, ry = y;
				}
			}
			printf("%d\n", res);
			// LOG("%d\n", min(n * (m - m / 4), m * (n - n / 4)));
			// LOG("+(%d, %d)\n", rx, ry);
			for (int i = 1; i <= n; ++i) {
				for (int j = 1; j <= m; ++j) {
					putchar(gr[rx + i][ry + j]);
				}
				puts("");
			}
		}
	}
	return 0;
}