CSES - Aalto Competitive Programming 2026 - wk2 - Homework

Submission details
Task:	Apartments
Sender:	aalto26bm_025
Submission time:	2026-09-09 10:51:56 +0300
Language:	Python3 (PyPy3)
Status:	READY
Result:	RUNTIME ERROR

Test results
test	verdict	time
#1	RUNTIME ERROR	0.06 s	details
#2	RUNTIME ERROR	0.06 s	details
#3	RUNTIME ERROR	0.06 s	details
#4	RUNTIME ERROR	0.06 s	details
#5	TIME LIMIT EXCEEDED	--	details
#6	TIME LIMIT EXCEEDED	--	details
#7	TIME LIMIT EXCEEDED	--	details
#8	RUNTIME ERROR	0.14 s	details
#9	RUNTIME ERROR	0.06 s	details
#10	RUNTIME ERROR	0.06 s	details
#11	RUNTIME ERROR	0.06 s	details
#12	RUNTIME ERROR	0.06 s	details
#13	RUNTIME ERROR	0.15 s	details
#14	RUNTIME ERROR	0.15 s	details
#15	RUNTIME ERROR	0.15 s	details
#16	RUNTIME ERROR	0.15 s	details
#17	WRONG ANSWER	0.15 s	details
#18	WRONG ANSWER	0.04 s	details
#19	RUNTIME ERROR	0.06 s	details

Code

import sys

def main():
    input_data = sys.stdin.read().split()
    if not input_data:
        return

    n = int(input_data[0])
    m = int(input_data[1])

    adj = [[] for _ in range(n + 1)]
    idx = 2
    for _ in range(m):
        u = int(input_data[idx])
        v = int(input_data[idx + 1])
        adj[u].append(v)
        adj[v].append(u)
        idx += 2

    visited = [False] * (n + 1)
    representatives = []
    stack = []

    for i in range(1, n + 1):
        if not visited[i]:
            representatives.append(i)
            stack.append(i)

            while stack:
                curr = stack.pop()
                visited[curr] = True
                for neighbor in adj[curr]:
                    if not visited[neighbor]:
                        stack.append(neighbor)

    k = len(representatives) - 1
    print(k)

    for i in range(k):
        print(f"{representatives[i]} {representatives[i + 1]}")

if __name__ == '__main__':
    main()

Test details

Test 1

Verdict: RUNTIME ERROR

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
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 2

Verdict: RUNTIME ERROR

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
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 3

Verdict: RUNTIME ERROR

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
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

Test 4

Verdict: RUNTIME ERROR

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
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

Test 5

Verdict: TIME LIMIT EXCEEDED

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

correct output
`197286` view save

user output
(empty)

Test 6

Verdict: TIME LIMIT EXCEEDED

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

correct output
`200000` view save

user output
(empty)

Test 7

Verdict: TIME LIMIT EXCEEDED

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

correct output
`200000` view save

user output
(empty)

Test 8

Verdict: RUNTIME ERROR

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

correct output
`200000` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

Test 9

Verdict: RUNTIME ERROR

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

correct output
`0` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 10

Verdict: RUNTIME ERROR

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

correct output
`0` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 11

Verdict: RUNTIME ERROR

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

correct output
`0` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

Test 12

Verdict: RUNTIME ERROR

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

correct output
`10` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

Test 13

Verdict: RUNTIME ERROR

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

correct output
`42` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 14

Verdict: RUNTIME ERROR

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

correct output
`846` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 15

Verdict: RUNTIME ERROR

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

correct output
`57149` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 17, in main
    adj[v].append(u)
IndexError: list index out of range

Test 16

Verdict: RUNTIME ERROR

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

correct output
`200000` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

Test 17

Verdict: WRONG ANSWER

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

correct output
`1` view save

user output
`199997 1 2 2 3 3 4 4 5 ...` 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 1 2 2 3 3 4 4 5` view save

Feedback: Output is longer than expected

Test 19

Verdict: RUNTIME ERROR

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

correct output
`2` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 43, in <module>
    main()
  File "/box/input/code.py", line 16, in main
    adj[u].append(v)
IndexError: list index out of range

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 (aalto26bm_025)