Submission #638305

#	Time	Username	Problem	Language	Result	Execution time	Memory
638305		jamezzz	Thousands Islands (IOI22_islands)	C++17	0 / 100	39 ms	11136 KiB

islands

#include "islands.h"
#include <bits/stdc++.h>
using namespace std;

#define maxn 100005

vector<int> AL[maxn],ans;
vector<pair<int,int>> num[maxn];

bool dfs(int u,int p){
	if(u==0&&AL[u].size()>=2){
		int a,b,c,d;
		tie(a,b)=num[u][0];
		tie(c,d)=num[u][1];
		ans={a,b,c,d,b,a,d,c};
		return true;
	}
}

variant<bool,vector<int>> find_journey(int N,int M,vector<int> U,vector<int> V){
	for(int i=0;i<M;i+=2){
		AL[U[i]].push_back(V[i]);
		AL[V[i]].push_back(U[i]);
		num[U[i]].push_back({i,i+1});
		num[V[i]].push_back({i+1,i});
	}
	if(dfs(0,-1))return ans;
	return false;
}

Compilation message (stderr)

islands.cpp: In function 'bool dfs(int, int)':
islands.cpp:18:1: warning: control reaches end of non-void function [-Wreturn-type]
   18 | }
      | ^

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