#include "september.h"
#include <bits/stdc++.h>
using namespace std;
void dfs(int u, int v, vector<vector<int>> &adj, vector<bool> &disconnected, vector<bool> &cleared, int ptr){
if(!cleared[u]){
if(disconnected[u] == 0) ptr ++;
disconnected[u] = 1;
for(int i = 0; i < adj[u].size(); i ++){
dfs(adj[u][i], u, adj, disconnected, cleared, ptr);
}
}
}
int solve(int N, int M, vector<int> F, vector<vector<int>> S) {
vector<vector<int>> adj(N, vector<int>());
for(int i = 1; i < F.size(); i ++){
adj[F[i]].push_back(i);
}
vector<vector<bool>> disconnected(M, vector<bool>(N, 0));
vector<int> nds(M, 0);
vector<vector<bool>> cleared(M, vector<bool>(N, 0));
int days = 0;
for(int i = 0; i < S[0].size(); i ++){
for(int j = 0; j < S.size(); j ++){
//dfs(S[j][i], 0, adj, disconnected[j], cleared[j], nds[j]);
if(disconnected[j][S[j][i]] == 1) nds[j] --;
disconnected[j][S[j][i]] = 0;
cleared[j][S[j][i]] = 1;
}
int newday = 1;
for(int j = 0; j < S.size(); j ++){
if(newday){
if(j != 0){
if(cleared[j] != cleared[j-1]){
newday = 0;
}
}
}
if(nds[j] != 0){
newday = 0;
}
}
days += newday;
}
return days;
}
/*
g++ -std=gnu++17 -O2 -o september stub.cpp september.cpp
1
5 2
0 0 2 2
3 2 1 4
2 3 1 4
*/
