Pretests

//Make CSP great again
#include <bits/stdc++.h>
#define TASK "TESTCODE"
using namespace std;
const int N = 20, M = 2e5;
int n, m, mask[M + 1], res, dp[N + 1][1 << N], Trace[1 << N], StartMask = 0, AddToRes;
char a[N][M];
vector<int> Adj[N];
set<int> FullAC;
void read()
{
   cin >> m >> n;
   AddToRes = 0;
   StartMask = 0;
   for (int i = 0; i < n; ++ i)
   {
       bool flag = false;
       for (int j = 0; j < m; ++ j)
       {
           cin >> a[i][j];
           if (a[i][j] == '0')
           {
               flag = true;
               mask[j] |= 1 << i;
               Adj[i].push_back(j);
           }
       }
       if (!flag)
       {
           FullAC.insert(i + 1);
           StartMask |= (1 << i);
           AddToRes += m;
       }
   }
   memset(dp, -1, sizeof(dp));
}
int f(int layer, int bitmask)
{
    if (bitmask == (1 << n) - 1)
    {
        return 0;
    }
    int &res = dp[layer][bitmask];
    if (res != -1)
    {
        return res;
    }
    res = 1e9;
    for (int i = 0; i < n ; ++ i)
    {
        if ((bitmask & (1 << i)) == 0)
        {
            for (int v : Adj[i])
            {
                int add = 0;
                for (int k = 0; k < n; ++ k)
                {
                    if (((mask[v] & (1 << k)) != 0) && ((bitmask & (1 << k)) == 0))
                    {
                        add += layer;
                    }
                }
                res = min(res, f(layer + 1, bitmask | mask[v]) + add);
            }
        }
    }
    return res;
}
void solve()
{
   cout << f(1, StartMask) + AddToRes << '\n';
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    freopen(TASK".INP", "r", stdin);
    //freopen(TASK".OUT", "w", stdout);
    int t = 1;
    bool typetest = true;
    if (typetest)
    {
        cin >> t;
    }
    for (int __ = 1; __ <= t; ++ __)
    {
        read();
        solve();
    }
}