#include <bits/stdc++.h>
#include "september.h"
using namespace std;
const int MAXN = 1e3 + 11;
int p[MAXN];
int id[7][MAXN], dp[MAXN];
bool mrk[7][MAXN], can[MAXN][MAXN];
set < int > st;
void up(int v, int k){
if(v == 0 || mrk[k][v]) return;
// cout << "Bad parent: " << v << ' ' << id[k][v] << '\n';
st.insert(id[k][v]), mrk[k][v] = 1;
up(p[v], k);
}
int solve(int N, int M, vector<int> F, vector<vector<int>> S) {
for(int i = 0; i < N; i++) p[i] = F[i], dp[i] = 0;
for(int i = 0; i < M; i++)
for(int j = 0; j < N - 1; j++)
id[i][S[i][j]] = j;
for(int i = 0; i < N - 1; i++){
st.clear();
for(int i = 0; i < M; i++)
for(int j = 0; j < N; j++)
mrk[i][j] = 0;
for(int j = N - 2; j >= i; j--){
auto it = st.lower_bound(i);
// if(it != st.end()) cout << *it << ' ' << "Sigma\n";
if(it == st.end() || *it > j) can[i][j] = 1;
else can[i][j] = 0;
// if(can[i][j]) cout << "Good: " << i << ' ' << j << '\n';
// for(auto it : st) cout << it << ' ';
// cout << '\n';
for(int k = 0; k < M; k++) up(S[k][j], k);
}
}
for(int i = 0; i < N - 1; i++)
if(can[0][i])
dp[i] = 1;
for(int i = 0; i < N - 1; i++)
for(int j = 0; j < i; j++)
if(dp[j] && can[j + 1][i])
dp[i] = max(dp[i], dp[j] + 1);
return dp[N - 2];
}
/*
void taskcase() {
int N, M;
assert(2 == scanf("%d%d", &N, &M));
std::vector<int> F(N);
F[0] = -1;
for (int i = 1; i < N; ++i)
assert(1 == scanf("%d", &F[i]));
vector<vector<int>> S((M), vector<int>(N - 1));
for (int i = 0; i < M; ++i){
for (int j = 0; j < N - 1; ++j)
scanf("%d", &S[i][j]);
}
printf("%d\n", solve(N, M, F, S));
}
int main() {
int T;
scanf("%d", &T);
while(T--) taskcase();
return 0;
}
*/
