#include "september.h"
#include <bits/stdc++.h>
using namespace std;
vector<vector<int>> ch;
vector<bool> vis, passed;
queue<int> q;
void dfs(int node){
	vis[node] = true;
	for(int i : ch[node]){
		if(!vis[i]) dfs(i);
	}
	q.push(node);
}
int solve(int N, int M, vector<int> F, vector<vector<int>> S) {
	ch.clear(), ch.resize(N);
	int k, ans = N+1;
	for(int i = 1; i < N; ++i){
		ch[F[i]].push_back(i);
	}
	for(int i = 0; i < M; ++i){
		k = 0;
		vis.assign(N, false);
		passed.assign(N, false);
		for(int j = 0; j < N-1; ++j){
			passed[S[i][j]] = true;
			if(!vis[S[i][j]]) dfs(S[i][j]);
			while(!q.empty() && passed[q.front()]) q.pop();
			if(q.empty()) k++;
		}
		ans = min(ans, k);
	}
	return ans;
}
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