#include "september.h"
#include <bits/stdc++.h>
using namespace std;
#include <vector>
const int N = 1e5 + 10;
vector<int> adj[N];
int mx_id[N], mx_sub_id[N];
void dfs(int node, int parent){
mx_sub_id[node] = mx_id[node];
for(auto i : adj[node]){
if(i == parent) continue;
dfs(i, node);
mx_sub_id[node] = max(mx_sub_id[node], mx_sub_id[i]);
}
}
int solve(int N, int M, std::vector<int> F, std::vector<std::vector<int>> S) {
for(int i = 0; i < N; i++){
adj[i].clear();
mx_id[i] = -1;
mx_sub_id[i] = -1;
}
for(int i = 1; i < N; i++){
adj[F[i]].push_back(i);
adj[i].push_back(F[i]);
}
for(int i = 0; i < M; i++){
for(int j = 0; j < N - 1; j++){
mx_id[S[i][j]] = max(mx_id[S[i][j]], j);
}
}
dfs(0, 0);
int cur = 0, ans = 0;
for(int i = 0; i < N - 1; i++){
for(int j = 0; j < M; j++){
cur = max(cur, mx_sub_id[S[j][i]]);
}
if(cur == i) ans++;
}
return ans;
}
