Submission #630706

#	Time	Username	Problem	Language	Result	Execution time	Memory
630706		DanerZein	Thousands Islands (IOI22_islands)	C++17	1.75 / 100	32 ms	5288 KiB

islands

#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;
const int MAX_M=2e5+10;
vector<vii> G;
bool vis[MAX_N];
bool usa[MAX_M];
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;
}

• Subtask 1: 0 / 5
• Subtask 2: 1.75 / 5
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 45