#include "islands.h"
#include <bits/stdc++.h>
#include <variant>
#include <vector>
using namespace std;
typedef pair<int,int> ii;
typedef vector<ii> vii;
const int MAX_N=1010;
vector<vii> G;
bool vis[MAX_N];
bool usa[MAX_N];
void dfs(int u){
vis[u]=1;
for(auto &v:G[u]){
if(!vis[v.first]){
usa[v.second]=1;
dfs(v.first);
}
}
}
std::variant<bool, std::vector<int>> find_journey(
int N, int M, std::vector<int> U, std::vector<int> V) {
G.resize(N+1);
for(int i=0;i<M;i+=2){
G[U[i]].push_back(ii(V[i],i/2));
G[U[i+1]].push_back(ii(V[i+1],i/2));
}
memset(vis,0,sizeof vis);
dfs(0);
bool ci=0;
for(int i=0;i<N;i++){
if(vis[i]){
for(auto &v:G[i]){
if(vis[v.first] && !usa[v.second]){
ci=1;
break;
}
}
}
if(ci) break;
}
if(ci || G[0].size()>=2) return true;
return false;
}
