CSES - Aalto Competitive Programming 2024 - wk2 - Homework

CSES - Aalto Competitive Programming 2024 - wk2 - Homework - Results

Submission details
Task:	Connect cities
Sender:	Mojojijo
Submission time:	2024-09-09 11:24:31 +0300
Language:	CPython3
Status:	READY
Result:	RUNTIME ERROR

Test results
test	verdict	time
#1	ACCEPTED	0.02 s	details
#2	ACCEPTED	0.02 s	details
#3	ACCEPTED	0.02 s	details
#4	ACCEPTED	0.02 s	details
#5	ACCEPTED	0.02 s	details
#6	RUNTIME ERROR	0.76 s	details
#7	RUNTIME ERROR	0.78 s	details
#8	RUNTIME ERROR	0.77 s	details
#9	RUNTIME ERROR	0.76 s	details
#10	RUNTIME ERROR	0.77 s	details
#11	ACCEPTED	0.26 s	details
#12	ACCEPTED	0.02 s	details

Code

def connect_cities(n, roads):
    from collections import defaultdict

     # Adjacency list
    graph = defaultdict(list)
    for a,b in roads:
        graph[a].append(b)
        graph[b].append(a)

    visited = [False] * (n+1)
    components =[]

    def dfs(node, component):
        visited[node] = True
        component.append(node)
        for neighbour in graph[node]:
            if not visited[neighbour]:
                dfs(neighbour, component)

    for i in range(1, n+1):
        if not visited[i]:
            component = []
            dfs(i, component)
            components.append(component)

    return components

def find_roads_to_add(n, roads):
    components = connect_cities(n, roads)
    
    # If there's only one component, no new roads are needed
    if len(components) == 1:
        print(0)
        return

    # We need to connect each component to the next one
    required_roads = []
    for i in range(len(components) - 1):
        # Connect the first city in component[i] to the first city in component[i+1]
        city1 = components[i][0]
        city2 = components[i+1][0]
        required_roads.append((city1, city2))
    
    # Step 5: Output the number of roads and the roads themselves
    print(len(required_roads))
    for road in required_roads:
        print(road[0], road[1])

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

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

# print(roads)

find_roads_to_add(n, roads)

Test details

Test 1

Verdict: ACCEPTED

input
`10 10 2 5 5 6 1 4 6 8 ...` view save

correct output
`2 1 2 2 7` view save

user output
`2 1 2 2 7` view save

Test 2

Verdict: ACCEPTED

input
`10 10 3 9 6 8 9 10 7 8 ...` view save

correct output
`2 1 4 4 5` view save

user output
`2 1 4 4 5` view save

Test 3

Verdict: ACCEPTED

input
`10 10 7 9 1 7 1 3 3 4 ...` view save

correct output
`0` view save

user output
`0` view save

Test 4

Verdict: ACCEPTED

input
`10 10 4 8 5 9 4 9 2 7 ...` view save

correct output
`1 1 3` view save

user output
`1 1 3` view save

Test 5

Verdict: ACCEPTED

input
`10 10 4 9 2 4 7 10 1 8 ...` view save

correct output
`0` view save

user output
`0` view save

Test 6

Verdict: RUNTIME ERROR

input
`100000 200000 7233 22146 94937 96203 6133 10731 98737 99193 ...` view save

correct output
`4785 1 2 2 3 3 4 4 5 ...` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 58, in <module>
    find_roads_to_add(n, roads)
  File "/box/input/code.py", line 29, in find_roads_to_add
    components = connect_cities(n, roads)
  File "/box/input/code.py", line 23, in connect_cities
    dfs(i, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  [Previous line repeated 993 more times]
  File "/box/input/code.py", line 15, in dfs
    component.append(node)
RecursionError: maximum recursion depth exceeded while calling a Python object

Test 7

Verdict: RUNTIME ERROR

input
`100000 200000 92950 93575 24401 88897 41796 99364 47106 50330 ...` view save

correct output
`4868 1 2 2 7 7 9 9 15 ...` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 58, in <module>
    find_roads_to_add(n, roads)
  File "/box/input/code.py", line 29, in find_roads_to_add
    components = connect_cities(n, roads)
  File "/box/input/code.py", line 23, in connect_cities
    dfs(i, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  [Previous line repeated 993 more times]
  File "/box/input/code.py", line 15, in dfs
    component.append(node)
RecursionError: maximum recursion depth exceeded while calling a Python object

Test 8

Verdict: RUNTIME ERROR

input
`100000 200000 15637 76736 79169 98809 4382 86557 73383 77029 ...` view save

correct output
`4683 1 9 9 20 20 27 27 28 ...` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 58, in <module>
    find_roads_to_add(n, roads)
  File "/box/input/code.py", line 29, in find_roads_to_add
    components = connect_cities(n, roads)
  File "/box/input/code.py", line 23, in connect_cities
    dfs(i, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  [Previous line repeated 993 more times]
  File "/box/input/code.py", line 15, in dfs
    component.append(node)
RecursionError: maximum recursion depth exceeded while calling a Python object

Test 9

Verdict: RUNTIME ERROR

input
`100000 200000 47932 66981 86401 99942 4353 27841 60492 67345 ...` view save

correct output
`4807 1 6 6 7 7 11 11 12 ...` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 58, in <module>
    find_roads_to_add(n, roads)
  File "/box/input/code.py", line 29, in find_roads_to_add
    components = connect_cities(n, roads)
  File "/box/input/code.py", line 23, in connect_cities
    dfs(i, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  [Previous line repeated 993 more times]
  File "/box/input/code.py", line 15, in dfs
    component.append(node)
RecursionError: maximum recursion depth exceeded while calling a Python object

Test 10

Verdict: RUNTIME ERROR

input
`100000 200000 6554 44548 76413 98555 5447 59589 70166 74434 ...` view save

correct output
`4786 1 2 2 18 18 21 21 27 ...` view save

user output
(empty)

Error:

Traceback (most recent call last):
  File "/box/input/code.py", line 58, in <module>
    find_roads_to_add(n, roads)
  File "/box/input/code.py", line 29, in find_roads_to_add
    components = connect_cities(n, roads)
  File "/box/input/code.py", line 23, in connect_cities
    dfs(i, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  File "/box/input/code.py", line 18, in dfs
    dfs(neighbour, component)
  [Previous line repeated 993 more times]
  File "/box/input/code.py", line 15, in dfs
    component.append(node)
RecursionError: maximum recursion depth exceeded while calling a Python object

Test 11

Verdict: ACCEPTED

input
`100000 1 1 2` view save

correct output
`99998 1 3 3 4 4 5 5 6 ...` view save

user output
`99998 1 3 3 4 4 5 5 6 ...` view save

Test 12

Verdict: ACCEPTED

input
`10 9 2 5 5 6 1 4 6 8 ...` view save

correct output
`2 1 2 2 7` view save

user output
`2 1 2 2 7` view save

Aalto Competitive Programming 2024 - wk2 - Homework

Connect cities

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 (Mojojijo)