#include <bits/stdc++.h>
#define rep(i, a, b) for (int i = a, i##_ = b; i < i##_; ++i)

using namespace std;
const int N = 2e3 + 5;
const pair<int, int> S[][4] = {
    {{0, 0}, {0, 1}, {1, 1}, {2, 0}},   {{0, 0}, {0, 2}, {1, 1}, {1, 2}},
    {{0, 0}, {1, -1}, {2, -1}, {2, 0}}, {{0, 0}, {0, 1}, {1, 0}, {1, 2}},
    {{0, 0}, {0, 1}, {1, 0}, {2, 1}},   {{0, 0}, {0, 1}, {1, -1}, {1, 1}},
    {{0, 0}, {1, 1}, {2, 0}, {2, 1}},   {{0, 0}, {0, 2}, {1, 0}, {1, 1}}};
const array<int, 4> Sub[] = {
    // Sub[i] = {u, v, x, y}, T[i] = S[u] + Move(S[v], x, y)
    {0, 6, 1, 0}, {3, 5, 0, 2},
    {4, 7, 1, -1}, {4, 5, 1, 1},  {1, 2, 0, 1}, {7, 6, 0, 1},
    {3, 1, 1, 1}, {0, 2, 1, 0},  {5, 7, 0, -2}, {4, 6, 1, 1},
};
int n, m, a[N][N];
void print() {
    printf("%d\n", m);
    rep(i, 0, n) rep(j, 0, n) printf("%d%c", a[i][j], " \n"[j == n - 1]);
}
const int ans9[][9] = {
    { 0,  1,  1,  2, 12, 12,  3, 13,  3},
    {11,  1, 11, 12,  2, 12,  3,  3, 13},
    {11, 11,  1,  2,  2,  4,  4, 13, 13},
    { 5, 15,  5,  6,  6,  4, 14,  4, 14},
    {15,  5,  5, 16,  6,  7,  7, 14, 14},
    {15, 15, 16,  6, 17,  7, 17,  8,  8},
    { 9,  9, 16, 16, 17, 17,  7,  8, 18},
    {19,  9, 19, 10, 20, 10, 20, 18,  8},
    { 9, 19, 19, 10, 10, 20, 20, 18, 18},
};
void fS(int x, int y, int k) {
    ++m;
    rep(i, 0, 4) a[x + S[k][i].first][y + S[k][i].second] = m;
}
void fT(int x, int y, int k) {
    auto [u, v, dx, dy] = Sub[k];
    fS(x, y, u), fS(x + dx, y + dy, v);
}
void Solve() {
    scanf("%d", &n), m = 0;
    rep(i, 0, n) fill(a[i], a[i] + n, 0);
    switch (n % 2) {
    case 0:
        int k = n % 4;
        rep(i, 0, n / 2) rep(j, 0, (n - k) / 4)
            fT(i * 2, j * 4, 1);
        if (k)
            for (int i = 0, j = n - k; i < n - k; i += 4)
                fT(i, j, 0);
        break;
    case 1:
        if (n == 3) fT(0, 0, 3);
        else if (n == 5 || n == 7) {
            fS(0, 3, 0), fS(1, 0, 0), fS(1, 2, 4), fS(3, 1, 4), fS(3, 3, 5);
            if (n == 7) fT(0, 5, 0), fT(5, 0, 1), fT(4, 5, 2);
        }
        if (n < 9) break;
        int k = n % 4 - 1, t = (n - k - 9) / 2;
        n -= k, m = 20;
        rep(i, 0, 9) rep(j, 0, 9) a[t + i][j] = ans9[i][j];
        for (int i = t - 2, r = t + 9; i >= 0; i -= 2, r += 2) {
            int cnt = (t - i) / 2 + 1, c = cnt * 4;
            rep(j, 0, cnt) fT(i, j * 4, 1), fT(r, j * 4, 1);
            rep(k, 0, cnt) fT(i + 4 * k, c + 3, 0);
            rep(k, 0, cnt - 1) fT(i + 3 + 4 * k, c + 1, 0);
            fT(i, c, 5), fT(r - 2, c + 1, 7), fT(r - 1, c + 3, 2), fT(r - 4, c + 1, 6);
        }
        if (k) {
            fT(n - 1, n, 2);
            rep(i, 0, (n - 1) / 4) fT(i * 4, n, 0), fT(n, i * 4, 1);
            n += k;
        }
        break;
    }
    print();
}
int main() {
    int t = 1;
    scanf("%d", &t);
    while (t--) Solve();
    return 0;
}

answer.code: In function ‘void Solve()’:
answer.code:53:10: error: jump to case label
   53 |     case 1:
      |          ^
answer.code:46:13: note:   crosses initialization of ‘int k’
   46 |         int k = n % 4;
      |             ^
answer.code:60:13: error: redeclaration of ‘int k’
   60 |         int k = n % 4 - 1, t = (n - k - 9) / 2;
      |             ^
answer.code:46:13: note: ‘int k’ previously declared here
   46 |         int k = n % 4;
      |             ^
answer.code:42:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   42 |     scanf("%d", &n), m = 0;
      |     ~~~~~^~~~~~~~~~
answer.code: In function ‘int main()’:
answer.code:81:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   81 |     scanf("%d", &t);
      |     ~~~~~^~~~~~~~~~