#include <bits/stdc++.h>
#include <algorithm>
#include <vector>
#include <map>

#define endl '\n'
#define ll long long
#define ld long double
#define P pair<ll, ll>
using namespace std;

int main()
{
    ll t;
    cin >> t;
    while (t--)
    {
        ll n, m;
        cin >> n >> m;
        //ll a[n][m], b[n][m];
        char a[n + 25][m + 25], b[n + 25][m + 25];
        for (ll i = 0; i < n; i++)
            cin >> a[i];

        for (ll i = 0; i < n; i++)
            cin >> b[i];
        ll dr = 0, dc = 0;
        ll errormin = n * m;
        //cout << "---\n";
        for (dr = 0; dr <= n; dr++)
        {
            for (dc = 0; dc <= m; dc++)
            {
                ll error = 0;
                for (ll i = 0; i < n; i++)
                {
                    for (ll j = 0; j < m; j++)
                    {
                        ll fdr = i + dr;
                        ll fdc = j + dc;
                        char temp = '0';
                        if (fdr >= n || fdc >= m)
                            temp = '0';
                        else
                            temp = b[i + dr][j + dc];
                        if (a[i][j] != temp)
                            error++;
                    }
                }
                if (error < errormin)
                    errormin = error;
                //cout << dr << " " << dc << " " << error << endl;
            }
        }
        for (dr = 0; dr >= -n; dr--)
        {
            for (dc = 0; dc >= -m; dc--)
            {
                ll error = 0;
                for (ll i = 0; i < n; i++)
                {
                    for (ll j = 0; j < m; j++)
                    {
                        ll fdr = i + dr;
                        ll fdc = j + dc;
                        char temp = '0';
                        if (fdr < 0 || fdc < 0)
                            temp = '0';
                        else
                            temp = b[i + dr][j + dc];
                        if (a[i][j] != temp)
                            error++;
                        // if (dr == -1 && dc == -1 && (a[i][j] != temp))
                        // {
                        //     cout << i << " " << j << " " << a[i][j] << " " << temp << endl;
                        // }
                    }
                }
                if (error < errormin)
                    errormin = error;

                //cout << dr << " " << dc << " " << error << endl;
            }
        }
        // cout << "====";
        cout << errormin << endl;
    }
}