CSES - Aalto Competitive Programming 2026 - wk2 - Homework

Submission details
Task:	Apartments
Sender:	aalto26bh_034
Submission time:	2026-09-06 21:20:03 +0300
Language:	C++ (C++23)
Status:	READY
Result:	WRONG ANSWER

Test results
test	verdict	time
#1	WRONG ANSWER	0.01 s	details
#2	WRONG ANSWER	0.00 s	details
#3	WRONG ANSWER	0.00 s	details
#4	WRONG ANSWER	0.00 s	details
#5	WRONG ANSWER	0.24 s	details
#6	WRONG ANSWER	0.26 s	details
#7	WRONG ANSWER	0.24 s	details
#8	WRONG ANSWER	0.24 s	details
#9	WRONG ANSWER	0.00 s	details
#10	WRONG ANSWER	0.00 s	details
#11	WRONG ANSWER	0.00 s	details
#12	WRONG ANSWER	0.00 s	details
#13	TIME LIMIT EXCEEDED	--	details
#14	TIME LIMIT EXCEEDED	--	details
#15	TIME LIMIT EXCEEDED	--	details
#16	TIME LIMIT EXCEEDED	--	details
#17	WRONG ANSWER	0.14 s	details
#18	WRONG ANSWER	0.00 s	details
#19	WRONG ANSWER	0.00 s	details

Code

#include <string>
#include <iostream>
#include <vector>
#include <utility>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>


using namespace std;

int main()
{
    int n_cities;
    int n_roads;
    cin >> n_cities >> n_roads;
    

    unordered_map<int, unordered_set<int>> city_map;
    unordered_set<int> seen_cities;     

    int road1, road2;

    for(int i = 0; i < n_roads; i++)
    {
        bool in = false;
        int temp_key;
        cin >> road1 >> road2;

        for(auto & [key, val] : city_map)
        {
            if(seen_cities.find(road1) == seen_cities.end() && seen_cities.find(road2) == seen_cities.end()) break;
            if(val.find(road1) != val.end() || val.find(road2) != val.end())
            {
                val.insert(road1);
                val.insert(road2);
                if(!in)
                {
                    temp_key = key, in = true;
                    if(!(seen_cities.find(road1) != seen_cities.end() && seen_cities.find(road2) != seen_cities.end())) break;
                }
                else
                {
                    city_map[temp_key].merge(val);
                    city_map.erase(key);
                    break;
                }
            }
        }
        if(!in)
        {
            unordered_set<int> temp = {road1, road2};
            city_map[road1] = temp;
        }
        seen_cities.insert(road1);
        seen_cities.insert(road2);
    }
    for(int i = 1; i <= n_cities; i++)
    {
        if(!seen_cities.count(i))
        {
            city_map[i] = {i};
        }
    }
    printf("%ld\n", city_map.size() - 1);
    unordered_map<int, unordered_set<int>>::iterator it1;
    unordered_map<int, unordered_set<int>>::iterator it2 = city_map.begin();
    it2++;
    for(it1 = city_map.begin(); it2 != city_map.end(); ++it1, ++it2)
    {
        printf("%d %d\n", *(it1->second.begin()), *(it2->second.begin()));
    }

}

Test details

Test 1

Verdict: WRONG ANSWER

input
`10 10 0 37 62 56 69 34 46 10 86 16 49 50 95 47 43 9 62 83 71 71 7` view save

correct output
`1` view save

user output
`16 7 6 6 5 5 37 37 50 ...` view save

Feedback: Output is longer than expected

Test 2

Verdict: WRONG ANSWER

input
`10 10 10 90 41 20 39 49 21 35 31 74 86 14 24 24 7 82 85 82 4 60 95` view save

correct output
`6` view save

user output
`15 9 8 8 6 6 20 20 90 ...` view save

Feedback: Output is longer than expected

Test 3

Verdict: WRONG ANSWER

input
`10 10 1000 59 5 65 15 42 81 58 96 50 1 18 59 71 65 97 83 80 68 92 67` view save

correct output
`10` view save

user output
`15 8 71 71 97 97 9 9 50 ...` view save

Feedback: Output is longer than expected

Test 4

Verdict: WRONG ANSWER

input
`10 10 1000000000 25 80 59 43 67 21 77 5 8 99 66 41 62 24 88 55 1 53 50 60` view save

correct output
`10` view save

user output
`16 10 9 9 7 7 6 6 25 ...` view save

Feedback: Output is longer than expected

Test 5

Verdict: WRONG ANSWER

input
`200000 200000 0 34 48 12 99 89 71 20 7 9 38 58...` view save

correct output
`197286` view save

user output
`199900 200000 199999 199999 199998 199998 199997 199997 199996 ...` view save

Feedback: Output is longer than expected

Test 6

Verdict: WRONG ANSWER

input
`200000 200000 10 89 26 46 74 91 19 47 18 83 85 ...` view save

correct output
`200000` view save

user output
`199900 200000 199999 199999 199998 199998 199997 199997 199996 ...` view save

Feedback: Output is longer than expected

Test 7

Verdict: WRONG ANSWER

input
`200000 200000 1000 71 84 11 90 70 59 60 11 52 65 ...` view save

correct output
`200000` view save

user output
`199899 200000 199999 199999 199998 199998 199997 199997 199996 ...` view save

Feedback: Output is longer than expected

Test 8

Verdict: WRONG ANSWER

input
`200000 200000 1000000000 21 94 92 4 12 5 38 47 59 92 2 ...` view save

correct output
`200000` view save

user output
`199900 200000 199999 199999 199998 199998 199997 199997 199996 ...` view save

Feedback: Output is longer than expected

Test 9

Verdict: WRONG ANSWER

input
`10 10 0 727245017 647121519 549745115 ...` view save

correct output
`0` view save

user output
`19 10 9 9 8 8 7 7 5 ...` view save

Feedback: Output is longer than expected

Test 10

Verdict: WRONG ANSWER

input
`10 10 10 30734435 218114477 257355293 4...` view save

correct output
`0` view save

user output
`18 9 8 8 5 5 30734435 30734435 6 ...` view save

Feedback: Output is longer than expected

Test 11

Verdict: WRONG ANSWER

input
`10 10 1000 7899629 162004163 327616450 51...` view save

correct output
`0` view save

user output
`19 10 9 9 8 8 7 7 6 ...` view save

Feedback: Output is longer than expected

Test 12

Verdict: WRONG ANSWER

input
`10 10 1000000000 725746771 537157640 742868604 ...` view save

correct output
`10` view save

user output
`19 8 6 6 5 5 4 4 725746771 ...` view save

Feedback: Output is longer than expected

Test 13

Verdict: TIME LIMIT EXCEEDED

input
`200000 200000 0 375495587 322263536 985991668 ...` view save

correct output
`42` view save

user output
(empty)

Test 14

Verdict: TIME LIMIT EXCEEDED

input
`200000 200000 10 906603621 968136956 666786366 ...` view save

correct output
`846` view save

user output
(empty)

Test 15

Verdict: TIME LIMIT EXCEEDED

input
`200000 200000 1000 215460174 880023362 242442952 ...` view save

correct output
`57149` view save

user output
(empty)

Test 16

Verdict: TIME LIMIT EXCEEDED

input
`200000 200000 1000000000 50349580 773460492 440699400 8...` view save

correct output
`200000` view save

user output
(empty)

Test 17

Verdict: WRONG ANSWER

input
`199999 1 1 199996 199997 149999 117797 19...` view save

correct output
`1` view save

user output
`199997 199999 199998 199998 199997 199997 199995 199995 199994 ...` view save

Feedback: Output is longer than expected

Test 18

Verdict: WRONG ANSWER

input
`5 2 2 2 2 2 40 50 40 50` view save

correct output
`2` view save

user output
`4 5 4 4 3 3 1 1 2` view save

Feedback: Output is longer than expected

Test 19

Verdict: WRONG ANSWER

input
`4 3 5 60 45 80 60 30 60 75` view save

correct output
`2` view save

user output
`5 4 3 3 2 2 1 1 80 ...` view save

Feedback: Output is longer than expected

Aalto Competitive Programming 2026 - wk2 - Homework

Apartments

Code

Test details

Test 1

Test 2

Test 3

Test 4

Test 5

Test 6

Test 7

Test 8

Test 9

Test 10

Test 11

Test 12

Test 13

Test 14

Test 15

Test 16

Test 17

Test 18

Test 19

Tasks

Submissions (aalto26bh_034)