CSES - Aalto Competitive Programming 2024 - wk2 - Homework - Results
Submission details
Task:Connect cities
Sender:Mojojijo
Submission time:2024-09-09 11:24:05 +0300
Language:CPython3
Status:READY
Result:
Test results
testverdicttime
#10.02 sdetails
#20.02 sdetails
#3ACCEPTED0.02 sdetails
#40.02 sdetails
#5ACCEPTED0.02 sdetails
#60.60 sdetails
#70.62 sdetails
#80.61 sdetails
#90.62 sdetails
#100.61 sdetails
#110.02 sdetails
#120.02 sdetails

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:

input
10 10
2 5
5 6
1 4
6 8
...

correct output
2
1 2
2 7

user output
[(2, 5), (5, 6), (1, 4), (6, 8...

Test 2

Verdict:

input
10 10
3 9
6 8
9 10
7 8
...

correct output
2
1 4
4 5

user output
[(3, 9), (6, 8), (9, 10), (7, ...

Test 3

Verdict: ACCEPTED

input
10 10
7 9
1 7
1 3
3 4
...

correct output
0

user output
[(7, 9), (1, 7), (1, 3), (3, 4...

Test 4

Verdict:

input
10 10
4 8
5 9
4 9
2 7
...

correct output
1
1 3

user output
[(4, 8), (5, 9), (4, 9), (2, 7...

Test 5

Verdict: ACCEPTED

input
10 10
4 9
2 4
7 10
1 8
...

correct output
0

user output
[(4, 9), (2, 4), (7, 10), (1, ...

Test 6

Verdict:

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

correct output
4785
1 2
2 3
3 4
4 5
...

user output
[(7233, 22146), (94937, 96203)...

Test 7

Verdict:

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

correct output
4868
1 2
2 7
7 9
9 15
...

user output
[(92950, 93575), (24401, 88897...

Test 8

Verdict:

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

correct output
4683
1 9
9 20
20 27
27 28
...

user output
[(15637, 76736), (79169, 98809...

Test 9

Verdict:

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

correct output
4807
1 6
6 7
7 11
11 12
...

user output
[(47932, 66981), (86401, 99942...

Test 10

Verdict:

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

correct output
4786
1 2
2 18
18 21
21 27
...

user output
[(6554, 44548), (76413, 98555)...

Test 11

Verdict:

input
100000 1
1 2

correct output
99998
1 3
3 4
4 5
5 6
...

user output
[(1, 2)]

Test 12

Verdict:

input
10 9
2 5
5 6
1 4
6 8
...

correct output
2
1 2
2 7

user output
[(2, 5), (5, 6), (1, 4), (6, 8...