OTHS Coding Competition 1 (Mock CCC) J5 - Scavenger Hunt

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Points: 10 (partial)
Time limit: 1.0s
Java 3.0s
Python 5.0s
Memory limit: 512M

Author:
Problem type

You are participating in a scavenger hunt in a city with N buildings (1-indexed) and M two-way roads connecting buildings a_i and b_i, taking c_i minutes to travel. You are currently in building 1 and your goal is to obtain K items labelled from 1 to K which are scattered across the city, in order. The i^{th} item will be present in k_i buildings. Building 1 is guaranteed to never contain any items and a building may contain more than 1 item. For each item, you also have the option to stand still and create it yourself in m_i minutes. What is the minimum amount of time you need to obtain all K items?

Constraints

1 \le N, M \le 20\,000

1 \le a_i, b_i \le N

a_i \neq b_i

1 \le c_i \le 10^6

1 \le m_i \le 10^9

1 \le K \le 30

1 \le k_i < N

Building 1 will never contain any items.

Subtask 1 [4/15]

k_i = 1

A building will contain at most 1 item.

Subtask 2 [4/15]

m_i = 10^9

c_i \le 10^3

Subtask 3 [7/15]

No additional constraints.

Input Specification

The first line contains 3 integers, N, M, and K, the number of buildings, the number of roads, and the number of items you need to collect, respectively.

The next line contains K space separated integers, m_1, \dots, m_K, where m_i is the time it takes to build item i yourself.

The next line contains K space separated integers, k_1, \dots, k_K, where k_i is the number of buildings that contain item i.

The i^{th} of the next K lines contain k_i space separated integers, the buildings that contain item i.

The next M lines contain 3 space separated integers, a_i, b_i, and c_i, representing a two-way road between buildings a_i and b_i, taking c_i minutes to travel.

Output Specification

Output one integer, the minimum time it takes to obtain all K items in minutes.

Sample Input 1

4 4 3
9 10 10
1 1 1
3
4
2
1 2 3
2 3 5
2 4 4
3 4 10

Sample Output 1

20

Explanation for Sample Output 1

This sample case satisfies the condition of subtask 1.

The optimal way to obtain all items is:

  • Create item 1 yourself.
  • Go from building 1 to building 2.
  • Go from building 2 to building 4. Collect item 2 here.
  • Go from building 4 to building 2. Collect item 3 here.

In total, you take 9 + (3 + 4 + 4) = 20 minutes, which is the minimum time possible.

Sample Input 2

5 6 2
1000000000 1000000000
1 2
3
4 5
1 2 1
1 3 4
2 3 2
2 4 1
3 5 6
5 4 2

Sample Output 2

6

Explanation for Sample Output 2

This sample case satisfies the condition of subtask 2.

The optimal way to obtain all items is:

  • Go from building 1 to building 2.
  • Go from building 2 to building 3. Collect item 1 here.
  • Go from building 3 to building 2.
  • Go from building 2 to building 4. Collect item 2 here.

In total, you take 1 + 2 + 2 + 1 = 6 minutes, which is the minimum time possible.

Sample Input 3

4 6 3
3 3 5
2 3 1
2 3
2 3 4
3
1 2 4
1 3 10
2 3 6
1 4 2
2 4 3
3 4 8

Sample Output 3

9

Explanation for Sample Output 3

The optimal way to obtain all items is:

  • Go from building 1 to building 2. Collect item 1 and 2 here.
  • Create item 3 yourself.

In total, you take 4 + 5 = 9 minutes, which is the minimum time possible.


Comments


  • 1
    thunder200911133  commented on April 29, 2024, 7:33 p.m. edited

    If this questions let you collect items not in order, it will be a 12 or 15 points question