#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

typedef long double ld;
typedef long long ll;

void solve(vector<vector<ld>> &matrix, int i, int j) {
    ld max_val = max({matrix[i-1][j], matrix[i+1][j], matrix[i][j-1], matrix[i][j+1]});
    matrix[i][j] = max_val;
}

int main() {
    ll T;
    cin >> T;
    while (T--) {
        int n, m;
        cin >> n >> m;
        vector<vector<ld>> matrix(n + 2, vector<ld>(m + 2, 0)); // Added padding to avoid boundary check

        for (int i = 1; i <= n; ++i) {
            for (int j = 1; j <= m; ++j) {
                cin >> matrix[i][j];
            }
        }

        for (int i = 1; i <= n; ++i) {
            for (int j = 1; j <= m; ++j) {
                ld a = matrix[i+1][j];
                ld b = matrix[i-1][j];
                ld c = matrix[i][j+1];
                ld d = matrix[i][j-1];
                ld e = matrix[i][j];
                if (e > a && e > b && e > c && e > d) {
                    solve(matrix, i, j);
                }
            }
        }

        for (int i = 1; i <= n; ++i) {
            for (int j = 1; j <= m; ++j) {
                cout << matrix[i][j] << " ";
            }
            cout << endl;
        }
    }
    return 0;
}