#include <bits/stdc++.h>
#define ll long long
using namespace std;
void paralysis(){
	int n,m,k;
	cin>>n>>m>>k;
	if (k>=m){
		cout<<m<<"\n";
		return;
	}
	
	vector<vector<int>> a(n+5,vector<int>(m+5));
	for (int i=1;i<=n*m;i++){
		int res;
		cin>>res;
		int x=(res-1)/m+1;
		int y=res-(x-1)*m;
		a[x][y]=i;
	}
	
	int ans=n*m;
	for (int i=1;i<=n;i++){
		sort(a[i].begin()+1,a[i].begin()+1+m);
		ans=min(ans,max(m,a[i][m-k]));
	}
	cout<<ans<<"\n";
}
/*
 3
 3 5 2
 1 4 13 6 8 11 14 2 7 10 3 15 9 5 12
 2 3 0
 1 6 4 3 5 2
 2 3 1000000000
 1 2 3 4 5 6
 
 1
 2 3 0
 1 6 4 3 5 2
*/
int main()
{
	ios::sync_with_stdio(0);
    cin.tie(0);
    
    int t=1;
    cin>>t;
	while (t--){
		paralysis();
	}
	return 0;
}