#include <bits/stdc++.h> using namespace std; int p[10001]; vector<vector<int>> a; vector<int> v; void dfs(int u, int k, int cnt){ v[u] = cnt; for(int e : a[u]) if(e != k) dfs(e, u, cnt + 1); } int send_message(int N, int i, int Pi) { p[i] = Pi; if(i == N - 1){ a.assign(N + 1, {}); v.assign(N + 1, 0); for(int j = 1; j <= N; j++){a[p[j]].push_back(j);} dfs(0, -1, 0); int mx = 1; for(int j = 2; j <= N; j++) if(v[j] > v[mx]) mx = j; return mx; } return 0; } pair<int, int> longest_path(vector<int> S) { return {0, S.back()}; }