CSES - Aalto Competitive Programming 2026 - wk2 - Mon

Submission details
Task:	Building Teams
Sender:	aalto26bm_033
Submission time:	2026-09-07 16:39:07 +0300
Language:	Python3 (PyPy3)
Status:	READY
Result:	WRONG ANSWER

Test results
test	verdict	time
#1	WRONG ANSWER	0.04 s	details
#2	WRONG ANSWER	0.04 s	details
#3	WRONG ANSWER	0.04 s	details
#4	WRONG ANSWER	0.04 s	details
#5	WRONG ANSWER	0.04 s	details
#6	WRONG ANSWER	0.36 s	details
#7	WRONG ANSWER	0.36 s	details
#8	WRONG ANSWER	0.36 s	details
#9	WRONG ANSWER	0.36 s	details
#10	WRONG ANSWER	0.28 s	details
#11	WRONG ANSWER	0.04 s	details
#12	WRONG ANSWER	0.04 s	details

Code

from collections import deque

n, m = map(int, input().split())

# adj list
adj = [[] for _ in range(n + 1)]

for _ in range(m):
    a, b = map(int, input().split())

    adj[a].append(b)
    adj[b].append(a)

def bipartite(n, adj):
    color = [-1] * (n + 1)

    for start in range(1, n + 1):
        if color[start] != -1:
            continue

        q = deque([start])
        color[start] = 0

        while q:
            u = q.popleft()

            for v in adj[u]:
                if color[v] == -1:
                    color[v] = color[u] ^ 1
                    q.append(v)

                elif color[v] == color[u]:
                    return None
    for i in range(len(color)):
        color[i] += 1
         
    return color[1:]

print(bipartite(n, adj))

Test details

Test 1

Verdict: WRONG ANSWER

input
`10 20 3 4 8 10 3 7 1 8 ...` view save

correct output
`1 1 1 2 2 1 2 2 2 1` view save

user output
`[1, 1, 1, 2, 2, 1, 2, 2, 2, 1]` view save

Test 2

Verdict: WRONG ANSWER

input
`10 20 1 3 8 10 2 4 6 8 ...` view save

correct output
`1 1 2 2 1 1 1 2 1 1` view save

user output
`[1, 1, 2, 2, 1, 1, 1, 2, 1, 1]` view save

Test 3

Verdict: WRONG ANSWER

input
`10 20 7 10 3 10 9 10 2 10 ...` view save

correct output
`1 2 2 1 1 1 2 1 2 1` view save

user output
`[1, 2, 2, 1, 1, 1, 2, 1, 2, 1]` view save

Test 4

Verdict: WRONG ANSWER

input
`10 20 2 4 2 10 7 10 4 6 ...` view save

correct output
`1 2 1 1 2 2 2 1 2 1` view save

user output
`[1, 2, 1, 1, 2, 2, 2, 1, 2, 1]` view save

Test 5

Verdict: WRONG ANSWER

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

correct output
`IMPOSSIBLE` view save

user output
`None` view save

Test 6

Verdict: WRONG ANSWER

input
`100000 200000 47355 96505 90709 92058 735 80715 91802 94265 ...` view save

correct output
`1 2 2 1 2 1 1 1 2 2 1 2 1 1 1 ...` view save

user output
`[1, 2, 2, 1, 2, 1, 1, 1, 2, 2,...` view save

Test 7

Verdict: WRONG ANSWER

input
`100000 200000 59991 95794 95150 96051 78453 94730 90411 95523 ...` view save

correct output
`1 1 1 2 2 1 1 2 1 2 1 2 2 2 1 ...` view save

user output
`[1, 1, 1, 2, 2, 1, 1, 2, 1, 2,...` view save

Test 8

Verdict: WRONG ANSWER

input
`100000 200000 89827 96402 65137 86792 80965 94708 19479 48078 ...` view save

correct output
`1 2 1 1 2 1 2 2 2 1 2 1 1 2 1 ...` view save

user output
`[1, 2, 1, 1, 2, 1, 2, 2, 2, 1,...` view save

Test 9

Verdict: WRONG ANSWER

input
`100000 200000 72952 83723 66197 70052 2949 52160 55753 95651 ...` view save

correct output
`1 1 2 2 2 1 1 2 2 2 2 2 1 2 1 ...` view save

user output
`[1, 1, 2, 2, 2, 1, 1, 2, 2, 2,...` view save

Test 10

Verdict: WRONG ANSWER

input
`100000 200000 38942 96755 70049 82663 7746 72732 87819 99029 ...` view save

correct output
`IMPOSSIBLE` view save

user output
`None` view save

Test 11

Verdict: WRONG ANSWER

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

correct output
`IMPOSSIBLE` view save

user output
`None` view save

Test 12

Verdict: WRONG ANSWER

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

correct output
`IMPOSSIBLE` view save

user output
`None` view save

Aalto Competitive Programming 2026 - wk2 - Mon

Building Teams

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

Tasks

Submissions (aalto26bm_033)