#include <bits/stdc++.h>

using namespace std;
using ll = long long;

int main()
{
    ll t;
    cin >> t;
    while (t-- > 0)
    {
        ll r, c;
        cin >> r >> c;
        vector<string> z1(r);                  // store keypad information
        vector<string> ans(r, string(c, 'N')); // for the visual output
        vector<string> ch(r, string(c, 'N'));  // for checking the existents of a button
        vector<ll> rw;
        vector<ll> cl;
        for (int i = 0; i < r; i++)
        {
            cin >> z1.at(i);
        }
        for (int i = 0; i < r; i++)
        {
            int hp = 0;
            for (int j = 0; j < c; j++)
            {
                if (hp >= 2)
                {
                    break;
                }
                if (z1.at(i).at(j) == '1')
                {
                    hp += 1;
                }
            }
            if (hp >= 2)
            {
                rw.push_back(1);
            }
            else
            {
                rw.push_back(0);
            }
        }
        for (int i = 0; i < c; i++)
        {
            int hp = 0;
            for (int j = 0; j < r; j++)
            {
                if (hp == 2)
                {
                    break;
                }
                if (z1.at(j).at(i) == '1')
                {
                    hp += 1;
                }
            }
            if (hp >= 2)
            {
                cl.push_back(1);
            }
            else
            {
                cl.push_back(0);
            }
        }
        for (int i = 0; i < r; i++)
        {
            for (int j = 0; j < c; j++)
            {
                if (z1.at(i).at(j) == '1')
                {
                    if (rw.at(i) == 1 && cl.at(j) == 1)
                    {
                        ans.at(i).at(j) = 'I';
                    }
                    else if (rw.at(i) == 1)
                    {
                        ans.at(i).at(j) = 'P';
                    }
                }
            }
        }
        if (ans == ch)
        {
            cout << "impossible" << endl;
        }
        else
        {
            for (int i = 0; i < r; i++)
            {
                cout << ans.at(i) << endl;
            }
        }

        cout << "----------" << endl;
    }
    return 0;
}