/**/
#include <bits/stdc++.h>
#define int long long
#define x first
#define y second
using namespace std;
using LL = long long;
typedef pair<int, int> PII;
const int N = 1e7 + 10, M = 5010, mod = 998244353;
const int inf = 1e9;
void solve() {
	int n, m, k;
	cin >> n >> m >> k;
	vector <int> a(n * m + 1);
	vector <vector<int>> row(n + 1);
	for(int i = 1; i <= n * m; i++){
		cin >> a[i];
		int p = (a[i] + m - 1) / m;
		if(row[p].size() < m - k) row[p].push_back(i);
	}
	/*for(int i = 1; i <= n; i++){
		for(auto u : row[i]){
			cout << u << " ";
		}
		cout << '\n';
	}*/
	int ans = inf;
	if(k >= m - 1) ans = m;
	for(int i = 1; i <= n; i++){
		int blank = 0, pre = 1;
		for(int j = 0; j < row[i].size(); j++){
			blank += row[i][j] - pre;
			pre = row[i][j];
		}
		int cost = 0;
		if(blank >= k) cost = pre;
		else{
			cost += k - blank + pre;
		}  
		ans = min(ans, cost);
	}
	cout << ans << "\n";
} 
signed main() {
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	int T = 1;
	cin >> T;
	while(T--) {
		solve();
	}
}