Submission #1077866

#	Time	Username	Problem	Language	Result	Execution time	Memory
1077866		pcc	Thousands Islands (IOI22_islands)	C++17	10 / 100	24 ms	9040 KiB

islands

#include "islands.h"

#include <variant>
#include <vector>
#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define fs first
#define sc second

std::variant<bool, std::vector<int>> find_journey(
    int N, int M, std::vector<int> U, std::vector<int> V) {
	if(N == 2){
		vector<int> cnt[2];
		for(int i = 0;i<M;i++){
			int a = U[i],b = V[i];
			cnt[a].push_back(i);
		}
		if(cnt[0].size()<2||cnt[1].size()<1)return false;
		int x = cnt[0][0],y = cnt[1][0],z = cnt[0][1];
		return vector<int>({x,y,z,x,y,z});
	}
	else{
		if(N<=2)return false;
		int mxn = 440;
		int arr[mxn][mxn];
		for(int i = 0;i<M;i++){
			int a = U[i],b = V[i];
			arr[a][b] = i;
		}
		pii a = pii(arr[0][1],arr[1][0]),b = pii(arr[1][2],arr[2][1]),c = pii(arr[2][0],arr[0][2]);
		return vector<int>({a.fs,b.fs,c.fs,c.sc,b.sc,a.sc,c.fs,b.fs,a.fs,a.sc,b.sc,c.sc});
	}
}

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:16:17: warning: unused variable 'b' [-Wunused-variable]
   16 |    int a = U[i],b = V[i];
      |                 ^

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