CSES - Aalto Competitive Programming 2025 - wk6 - Homework

Submission details
Task:	Course Schedule
Sender:	azeaus1
Submission time:	2025-10-04 18:32:53 +0300
Language:	Python3 (PyPy3)
Status:	READY
Result:	RUNTIME ERROR

Test results
test	verdict	time
#1	ACCEPTED	0.04 s	details
#2	ACCEPTED	0.04 s	details
#3	ACCEPTED	0.04 s	details
#4	ACCEPTED	0.04 s	details
#5	ACCEPTED	0.04 s	details
#6	ACCEPTED	0.56 s	details
#7	ACCEPTED	0.54 s	details
#8	ACCEPTED	0.54 s	details
#9	ACCEPTED	0.56 s	details
#10	RUNTIME ERROR	0.38 s	details
#11	ACCEPTED	0.32 s	details
#12	ACCEPTED	0.04 s	details
#13	ACCEPTED	0.04 s	details
#14	ACCEPTED	0.30 s	details
#15	RUNTIME ERROR	0.27 s	details
#16	ACCEPTED	0.04 s	details
#17	ACCEPTED	0.30 s	details

Code

n, m = [int(x) for x in input().split()]
order = []
in_process = set([])
processed = set([])
impossible = False

graph = [[] for _ in range(n)]
for i in range(m):
    a, b = [int(x) for x in input().split()]
    graph[b-1].append(a-1)

def dfs_rec(x):
    global impossible
    
    in_process.add(x)
    for c in graph[x]:
        if c in in_process:
            impossible = True
            break
        if c not in processed:
            dfs_rec(c)
    order.append(x+1)
    in_process.remove(x)
    processed.add(x)

for i in range(n):
    if i not in processed:
        dfs_rec(i)

if impossible:
    print('IMPOSSIBLE')
else:
    for course in order:
        print(course, end=' ')

Test details

Test 1

Verdict: ACCEPTED

input
`10 20 5 2 2 4 8 9 6 4 ...` view save

correct output
`5 7 10 2 1 8 3 9 6 4` view save

user output
`10 1 5 7 2 8 3 9 6 4` view save

Test 2

Verdict: ACCEPTED

input
`10 20 2 7 1 10 9 5 9 7 ...` view save

correct output
`1 8 3 6 10 2 9 4 5 7` view save

user output
`1 3 6 10 2 8 9 4 5 7` view save

Test 3

Verdict: ACCEPTED

input
`10 20 8 5 2 3 10 1 9 1 ...` view save

correct output
`4 6 7 9 10 2 8 3 1 5` view save

user output
`7 10 9 4 2 6 3 8 1 5` view save

Test 4

Verdict: ACCEPTED

input
`10 20 5 10 10 3 9 10 6 2 ...` view save

correct output
`7 8 6 4 2 1 5 9 10 3` view save

user output
`8 4 1 7 6 2 5 9 10 3` view save

Test 5

Verdict: ACCEPTED

input
`10 20 2 9 4 8 9 1 10 6 ...` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 6

Verdict: ACCEPTED

input
`100000 200000 78359 8853 18190 30703 11401 30087 34627 11535 ...` view save

correct output
`2 3 8 9 16 18 21 22 27 34 36 4...` view save

user output
`51177 42979 40727 29046 51923 ...` view save

Test 7

Verdict: ACCEPTED

input
`100000 200000 32395 2098 67067 31866 31867 67167 78488 33397 ...` view save

correct output
`9 11 13 16 22 35 37 38 40 44 5...` view save

user output
`73346 1 60874 8099 43686 54924...` view save

Test 8

Verdict: ACCEPTED

input
`100000 200000 19035 36947 13730 46121 99449 77790 15626 11731 ...` view save

correct output
`1 7 15 17 18 34 38 41 48 49 51...` view save

user output
`1 37848 2 4553 47278 64821 358...` view save

Test 9

Verdict: ACCEPTED

input
`100000 200000 14188 9709 46541 20871 32203 88809 99879 54779 ...` view save

correct output
`6 10 11 16 17 19 21 22 23 28 3...` view save

user output
`39668 83161 1 17892 1075 5973 ...` view save

Test 10

Verdict: RUNTIME ERROR

input
`100000 200000 41882 61162 28138 18053 74649 74863 69760 74508 ...` view save

correct output
`IMPOSSIBLE` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "input/code.py", line 28, in <module>
    dfs_rec(i)
  File "input/code.py", line 21, in dfs_rec
    dfs_rec(c)
  File "input/code.py", line 21, in dfs_rec
    dfs_rec(c)
  File "input/code.py", line 21, in dfs_rec
    dfs_rec(c)
  [Previous line repeated 1580 more times]
  File "input/code.py", line 15, in dfs_rec
    in_process.add(x)
RecursionError: maximum recursion depth exceeded

Test 11

Verdict: ACCEPTED

input
`100000 199998 1 100000 1 100000 2 100000 2 100000 ...` view save

correct output
`1 2 3 4 5 6 7 8 9 10 11 12 13 ...` view save

user output
`1 2 3 4 5 6 7 8 9 10 11 12 13 ...` view save

Test 12

Verdict: ACCEPTED

input
`2 2 1 2 2 1` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 13

Verdict: ACCEPTED

input
`6 6 1 2 2 3 4 3 4 5 ...` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 14

Verdict: ACCEPTED

input
`99999 149997 1 3 3 5 5 7 7 9 ...` view save

correct output
`1 2 3 4 5 6 7 8 9 10 11 12 13 ...` view save

user output
`1 2 3 4 5 6 7 8 9 10 11 12 13 ...` view save

Test 15

Verdict: RUNTIME ERROR

input
`100000 149998 2 1 3 2 4 3 5 4 ...` view save

correct output
`100000 99999 99998 99997 99996...` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "input/code.py", line 28, in <module>
    dfs_rec(i)
  File "input/code.py", line 21, in dfs_rec
    dfs_rec(c)
  File "input/code.py", line 21, in dfs_rec
    dfs_rec(c)
  File "input/code.py", line 21, in dfs_rec
    dfs_rec(c)
  [Previous line repeated 1576 more times]
  File "input/code.py", line 15, in dfs_rec
    in_process.add(x)
RecursionError: maximum recursion depth exceeded

Test 16

Verdict: ACCEPTED

input
`6 6 1 2 1 3 2 4 3 5 ...` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 17

Verdict: ACCEPTED

input
`100000 200000 1 1 1 1 2 2 2 2 ...` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Aalto Competitive Programming 2025 - wk6 - Homework

Course Schedule

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

Tasks

Submissions (azeaus1)