# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1239684 | AlperenT_ | Thousands Islands (IOI22_islands) | C++20 | 0 ms | 0 KiB |
#include "islands.h"
#include <variant>
#include <vector>
#include <bits/stdc++.h>
//#include "segments.h"
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2")
#define pb push_back
#define F first
#define pii pair<int,int>
#define all(a) a.begin(),a.end()
#define S second
#define sz(a) (int)a.size()
#define rep(i , a , b) for(int i = (a) ; i <= (b) ; i++)
#define per(i , a , b) for(int i = (a) ; i >= (b) ; i--)
#define ld double
#define ll long long
using namespace std ;
const int maxn = 1e6 + 10 , inf = 1e9+ 10 , mod = 998244353;
int mark[maxn] ;
vector <pii> G[maxn] ;
std::variant<bool, std::vector<int>> find_journey(int n, int m, std::vector<int> U, std::vector<int> V) {
rep(i , 0 ,m-1){
G[U[i]].pb({V[i] , i});
}
bool ok =0;
vector <int> vec ;
if(sz(G[0]) >= 2)return 1 ;
if(sz(G[0]) == 0)return 0 ;
int v =G[v][0].F ;
mark[0] = 1;
while(1){
int nx = -1;
mark[v] = 1;
for(auto [u,w] : G[V]){
if(nx!=-1 && mark[u] == 0)return 1 ;
if(mark[u] == 0)nx = u ;
}
v = nx ;
if(nx == -1)return 0 ;
}
return 1;
}