#include <bits/stdc++.h>

using namespace std;

int main() {

ios_base::sync_with_stdio(false);

cin.tie(nullptr);

int t;

cin >> t;

while (t--) {

int n, m;

cin >> n >> m;

vector<vector<int>> a(n, vector<int>(m));

int mx = 0, cnt_mx = 0;

for (int i = 0; i < n; i++) {

for (int j = 0; j < m; j++) {

cin >> a[i][j];

if (a[i][j] > mx) {

mx = a[i][j];

cnt_mx = 1;

} else if (a[i][j] == mx) {

cnt_mx++;

}

}

}

vector<int> rowCount(n, 0), colCount(m, 0);

for (int i = 0; i < n; i++) {

for (int j = 0; j < m; j++) {

if (a[i][j] == mx) {

rowCount[i]++;

colCount[j]++;

}

}

}

10

bool canReduce = false;

for (int i = 0; i < n; i++) {

for (int j = 0; j < m; j++) {

int totalCovered = rowCount[i] + colCount[j];

if (a[i][j] == mx) totalCovered--;

if (totalCovered == cnt_mx) {

canReduce = true;

break;

}

}

if (canReduce) break;

}

cout << mx - canReduce << '\n';

}

return 0;

}