Submission #685362

#	Time	Username	Problem	Language	Result	Execution time	Memory
685362		irmuun	Thousands Islands (IOI22_islands)	C++17	10 / 100	48 ms	24084 KiB

islands

#include<bits/stdc++.h>
#include "islands.h"
using namespace std;
#define pb push_back
variant<bool, vector<int>> find_journey(int N, int M, vector<int> U, vector<int> V){
	if(N==2){
		vector<int>v0,v1;
		for(int i=0;i<M;i++){
			if(U[i]==0){
				v0.pb(i);
			}
			else{
				v1.pb(i);
			}
		}
		if(v0.size()<2||v1.size()<1){
			return false;
		}
		return vector<int>{v0[0],v1[0],v0[1],v0[0],v1[0],v0[1]};
	}
	if(N<=1000&&M%2==0){
		vector<int>p[N+5][N+5];
		vector<int>vec;
		for(int i=0;i<M;i++){
			p[U[i]][V[i]].pb(i);
		}
		for(int i=1;i<N;i++){
			for(int j=0;j<min(p[i][0].size(),p[0][i].size());j++){
				vec.pb(p[0][i][j]);
				vec.pb(p[i][0][j]);
			}
		}
		if(vec.size()<4){
			return false;
		}
		return vector<int>{vec[0],vec[1],vec[2],vec[3],vec[1],vec[0],vec[3],vec[2]};
	}
	return false;
}

Compilation message (stderr)

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:28:17: warning: comparison of integer expressions of different signedness: 'int' and 'const long unsigned int' [-Wsign-compare]
   28 |    for(int j=0;j<min(p[i][0].size(),p[0][i].size());j++){
      |                ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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