Submission #1042497

#	Time	Username	Problem	Language	Result	Execution time	Memory
1042497		Alihan_8	Thousands Islands (IOI22_islands)	C++17	9.10 / 100	19 ms	4188 KiB

islands

#include "islands.h"

#include <variant>
#include <vector>

#include <bits/stdc++.h>

using namespace std;

#define pb push_back

template <class F, class S>
bool chmin(F &u, const S &v){
	bool flag = false;
	
	if ( u > v ){
		u = v; flag |= true;
	}
	
	return flag;
}

std::variant<bool, std::vector<int>> find_journey(
    int N, int M, std::vector<int> U, std::vector<int> V) {
  
	int n = N, m = M;
	
	// subtask #3
	
	vector <vector<int>> adj(n);
	
	for ( int i = 0; i < m; i++ ){
		adj[U[i]].pb(V[i]);
	}
	
	vector <int> d(n, n + 1);
	
	queue <int> q;
	
	q.push(0); d[0] = 0;
	
	bool has = false;
	
	while ( !q.empty() ){
		int u = q.front();
		q.pop();
		
		for ( auto &v: adj[u] ){
			if ( chmin(d[v], d[u] + 1) ){
				q.push(v);
			} else if ( d[v] == d[u] + 1 ){
				has = true;
			}
		}
	}
	
	set <int> st;
	
	int cnt = 0;
	
	for ( auto &x: d ){
		if ( x != n + 1 ){
			st.insert(x);
			
			cnt += 1;
		}
	}
	
	return ((int)st.size() != cnt || has);
}

• Subtask 1: 0 / 5
• Subtask 2: 1.75 / 5
• Subtask 3: 7.35 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 45