CSES - Aalto Competitive Programming 2024 - wk7 Homework - Results
Submission details
Task:Download Speed
Sender:louaha1
Submission time:2024-10-24 09:30:37 +0300
Language:Python3 (CPython3)
Status:READY
Result:
Test results
testverdicttime
#1ACCEPTED0.02 sdetails
#20.02 sdetails
#30.02 sdetails
#40.02 sdetails
#50.02 sdetails
#60.02 sdetails
#70.02 sdetails
#8ACCEPTED0.02 sdetails
#90.02 sdetails
#100.02 sdetails
#110.02 sdetails
#120.02 sdetails

Code

import heapq

def max_bandwidth(n, m, connections):
    adj = [[] for _ in range(n + 1)]
    
    # Build the adjacency list
    for a, b, c in connections:
        adj[a].append((b, c))
        adj[b].append((a, c))  # undirected graph

    # Dijkstra's algorithm with max-heap to maximize the minimum bandwidth
    max_bandwidth = [0] * (n + 1)
    max_bandwidth[1] = float('inf')  # Starting from node 1 with infinite bandwidth
    pq = [(-float('inf'), 1)]  # (bandwidth, node), using negative to simulate max-heap

    while pq:
        bw, node = heapq.heappop(pq)
        bw = -bw  # Convert back to positive value
        if bw < max_bandwidth[node]:
            continue

        # Traverse all the neighbors
        for neighbor, edge_bw in adj[node]:
            new_bw = min(bw, edge_bw)
            if new_bw > max_bandwidth[neighbor]:
                max_bandwidth[neighbor] = new_bw
                heapq.heappush(pq, (-new_bw, neighbor))

    return max_bandwidth[n]

# Input
n, m = map(int, input().split())
connections = [tuple(map(int, input().split())) for _ in range(m)]

# Find the maximum bandwidth path
result = max_bandwidth(n, m, connections)
print(result)

Test details

Test 1

Verdict: ACCEPTED

input
4 3
1 2 5
2 3 3
3 4 6

correct output
3

user output
3

Test 2

Verdict:

input
4 5
1 2 1
1 3 1
2 3 1
2 4 1
...

correct output
2

user output
1

Test 3

Verdict:

input
4 5
1 2 1000000000
1 3 1000000000
2 3 1
2 4 1000000000
...

correct output
2000000000

user output
1000000000

Test 4

Verdict:

input
2 1
2 1 100

correct output
0

user output
100

Test 5

Verdict:

input
2 1000
1 2 1000000000
1 2 1000000000
1 2 1000000000
1 2 1000000000
...

correct output
1000000000000

user output
1000000000

Test 6

Verdict:

input
500 998
1 2 54
1 3 59
1 4 83
2 5 79
...

correct output
60

user output
54

Test 7

Verdict:

input
500 998
1 2 530873053
1 3 156306296
1 4 478040476
3 5 303609600
...

correct output
1093765123

user output
688173231

Test 8

Verdict: ACCEPTED

input
2 1
1 2 1

correct output
1

user output
1

Test 9

Verdict:

input
4 5
1 2 3
2 4 2
1 3 4
3 4 5
...

correct output
6

user output
4

Test 10

Verdict:

input
4 5
1 2 1
1 3 2
3 2 1
2 4 2
...

correct output
3

user output
1

Test 11

Verdict:

input
10 999
1 2 1000000000
1 2 1000000000
1 2 1000000000
1 2 1000000000
...

correct output
111000000000

user output
1000000000

Test 12

Verdict:

input
7 9
1 2 1
1 3 1
1 4 1
2 5 1
...

correct output
2

user output
1