#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define pii pair<int, int>
#define ld long double
#define all(a) (a).begin(), (a).end()

void print(vector<string> ans, bool is_trans) {
    int n = ans.size(), m = ans[0].size();
    int cnt = 0;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            cnt += ans[i][j] - '0';
        }
    }
    cout << cnt << "\n";
    if (is_trans) swap(n, m);
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (is_trans) {
                cout << ans[j][i];
            } else {
                cout << ans[i][j];
            }
        }
        cout << "\n";
    }
}

vector<int> dx = {1, 0, -1, 0};
vector<int> dy = {0, 1, 0, -1};

int count(vector<string> arr) {
    int n = arr.size();
    int m = arr[0].size();
    vector<vector<int>> used(n, vector<int>(m, 0));
    deque<array<int, 2>> q;
    /// cerr << "start eval" << endl;
    for (int i = 0; i < n && q.empty(); ++i) {
        for (int j = 0; j < m && q.empty(); ++j) {
            if (arr[i][j] == '1') {
                q.push_back({i, j});
                used[i][j] = true;
                /// cerr << i << " " << j << endl;
            }
        }
    }
    while (!q.empty()) {
        auto elem = q.front();
        q.pop_front();
        int x = elem[0], y = elem[1];
        for (int t = 0; t < 4; ++t) {
            int x1 = x + dx[t];
            int y1 = y + dy[t];
            if (x1 < 0 || y1 < 0 || x1 >= n || y1 >= m) continue;
            if (arr[x1][y1] == '0') continue;
            if (!used[x1][y1]) {
                used[x1][y1] = true;
                q.push_back({x1, y1});
                /// cerr << x1 << " " << y1 << endl;
            }
        }
    }
    int cnt = 0;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (arr[i][j] == '1') {
                if (!used[i][j]) {
                    return -1;
                }
                ++cnt;
            }
        }
    }
    return cnt;
}

void solve() {
    int n, m;
    cin >> n >> m;
    bool is_trans = false;
    if (n > m) {
        is_trans = true;
        swap(n, m);
    }
    vector<string> ans;
    int cnt = 0;
    if (m < 4) {
        for (int i = 0; i < n; ++i) {
            ans.push_back(string(m, '1'));
        }
        print(ans, is_trans);
        return;
    }
    vector<int> ord = {0, 1, 2, 3};
    vector<string> row(4);
    for (int i = 0; i < 4; ++i) {
        for (int j = 0; j < m; ++j) {
            if (j % 4 == i) {
                row[i].push_back('0');
            } else {
                row[i].push_back('1');
            }
        }
    }
    do {
        vector<string> cur;
        for (int i = 0; i < n; ++i) {
            cur.push_back(row[ord[i % 4]]);
        }
        int res = count(cur);
        if (res > cnt) {
            cnt = res;
            ans = cur;
        }
    } while (next_permutation(ord.begin(), ord.end()));
    print(ans, is_trans);
}

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

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

    return 0;
}