#include "islands.h"
#include<bits/stdc++.h>
#include <variant>
#include <vector>
using namespace std;
const int N = 1010;
vector <pair <int, int>> g[N];
int mark[N], pai[N];
vector <int> ans;
int aresta[N][N];
std::variant<bool, std::vector<int>> find_journey(int N, int M, std::vector<int> U, std::vector<int> V) {
int n = N;
for(int i = 0;i < M;i++){
g[U[i]].push_back({V[i], i});
aresta[U[i]][V[i]] = i;
}
if(g[0].empty()) return false;
if(g[0].size() > 1){
int i = 0;
if(g[i].size() > 1){
vector <int> ans;
int a, b, c, d;
a = g[i][0].second;
c = g[i][1].second;
for(auto [u, id] : g[g[i][0].first]){
if(u == i) b = id;
}
for(auto [u, id] : g[g[i][1].first]){
if(u == i) d = id;
}
ans = {a, b, c, d, b, a, d, c};
return ans;
}
}
return false;
}
