#include<bits/stdc++.h>
#define ll long long
#define all(x) x.begin(), x.end()
#define lowbit(i) ((i)&(-i))
#define pii pair<int,int>
#define endl '\n'
#define mk(x,y) make_pair(x,y)
#define popcount(x) __builtin_popcount(x)
#define LF(x) fixed<<setprecision(x)
const double pi=3.14159265358979323846;
const double eps=1e-9;
const int inf=1e9;
const long long INF=4e18;
const int mod=1e9+7;
using namespace std;
const int N=1e5+10;

void solve()
{
    int n,m;
    cin>>n>>m;
    vector<vector<int>>a(n+1,vector<int>(m+1));
    map<int,array<int,2>>v;
    for(int i=1;i<=n;i++){
    	for(int j=1;j<=m;j++){
    		cin>>a[i][j];
    		v[a[i][j]]=(array<int,2>){i,j};
    	}
    }
    auto check=[&](int mid){
    	vector<array<int,2>>vv(mid);
    	for(int i=0;i<mid;i++){
    		vv[i]=v[i];
    	}
    	sort(vv.begin(),vv.end());
    	// if(mid==4)for(auto[x,y]:vv){
    	// 	cout<<x<<" "<<y<<endl;
    	// }
    	for(int i=1;i<mid;i++){
    		auto [x,y]=vv[i];
    		auto [x1,y1]=vv[i-1];
    		if(y1>y)return false;
    	}
    	return true;
    };
    int l=0,r=n*m;
    while(l<r){
    	int mid=(l+r+1)/2;
    	// cout<<mid<<endl;
    	if(check(mid))l=mid;
    	else r=mid-1;
    }
    cout<<l<<endl;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    
    int T=1;
    cin>>T;
    while(T--){
        solve();
    }
    return 0;
}