## DMOPC '15 Contest 3 P4 - Contagion

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Points: 12 (partial)
Time limit: 1.0s
Memory limit: 128M

Author:
Problem type

cheesecake works part-time at the Centre for Disease Control and Prevention (CDC), where he researches the spread of diseases. An unknown pathogen has just broken out and cheesecake is determined to save the world!

The CDC's model of the world consists of countries numbered through , represented by points on a 2-D coordinate plane. Country is located at integral coordinates .

Through extensive research, cheesecake has determined a vital piece of information: the time in hours it takes for the pathogen to spread from one country to another is equal to the square of the distance between the two countries. For example, if country is located at and country is located at , it will take hours for country to be infected after the initial infection of country . The source of the breakout, country , is infected at the -th hour.

In order to take preventative measures, cheesecake has been tasked with projecting the rate of infection. Specifically, he has to answer queries of the following form:

How many countries will be infected after hours?

Unfortunately, cheesecake isn't taking data management this semester, so he's at a total loss. Help him save the world!

,

,

,

,

,

,

#### Input Specification

The first line of input will contain , the number of countries.

The next lines will contain and , the coordinates of the -th country, it is guaranteed that no two countries will have the same coordinates.

The next line will contain , the source of the breakout.

The next line will contain , the number of queries.

The next lines will each contain a query.

#### Output Specification

For each query, output the answer on a new line.

#### Sample Input

4
2 2
0 3
5 1
4 0
1
4
8
10
4
7

#### Sample Output

3
4
1
2

#### Explanation for Sample Output

After hours, the pathogen has not yet spread from its source, therefore the answer is . After hours, country is infected. After hours, country is also infected. At hours, the pathogen has spread from country to country .

• commented on Feb. 29, 2020, 12:25 a.m.

Assuming the first test case is the test case, my clipped output does not match my output in the compiler. My program prints out "3 4 1 2" (on different lines) but the clipped output says "1 1 1 1" (on different lines).

• commented on Feb. 29, 2020, 12:29 a.m.

Your code has undefined behaviour. Your visited array needs to be initialized to a value, or else it will take whatever garbage values are currently stored at that memory address.

• commented on Dec. 4, 2017, 9:58 p.m.

What does "No judge is available for this problem." mean other than the obvious? Will I be able to submit later?

• commented on Dec. 4, 2017, 10:13 p.m.

And it's back up now. merp

• commented on Dec. 4, 2017, 10:11 p.m. edited

/

• commented on Dec. 3, 2017, 10:12 p.m.

No, it's simply referring to the query, since the explanation is not written in chronological order

• commented on Dec. 3, 2017, 9:15 p.m.

For the explanation for sample output, shouldn't the time it takes to get to country 2 be 5 hours, not 7 hours?

• commented on Nov. 5, 2017, 9:50 p.m. edited

NVM

fixed

• commented on Aug. 20, 2017, 12:54 a.m. edit 3

EDIT Make sure you use correct types!

• commented on June 17, 2017, 8:22 p.m.

Please, for the sanity of DMOJ programmers, allow submissions that don't pass the sample case to run on the other batches. It's a nightmare debugging an RTE with no output.

• commented on Jan. 5, 2016, 9:31 p.m.

Why are so many people (including myself) getting runtime error? :'(

• commented on Jan. 5, 2016, 10:09 p.m. edited

It's very expensive memory-wise to maintain a priority queue of up to edges. Even if I raise the memory limit to 1 GB, your solution will TLE. The editorial might help you.

Edit: I think it depends on which judge your submission was run on. 64-bit judges will give you RTE and 32-bit judges will give you TLE.

• commented on Jan. 5, 2016, 9:33 p.m. edit 6

It's probably because you're initializing a long long array of elements, although I didn't look at your code in detail enough to be sure.

Since a long long takes up bits of memory and you're allocating of them, that means you're using up bits, or bytes, or . That should technically pass the memory limit, maybe? But you'd be cutting it close with all of your other variables and arrays.

Be aware that if you wanted mathematical rigor, you should have specifically asked for Bruce or Jason's help. :)

Anyway, that might be why, or maybe I'm totally off. Cheers!

• commented on March 29, 2016, 8:27 p.m.

Bruce or Jason's help lol

• commented on Dec. 19, 2015, 1:44 p.m.

If you're getting TLE on Python, try using multiplication instead of power.

• commented on Dec. 18, 2015, 5:00 p.m.

I'm not sure if this is a bug or something, but the code can only be submitted in php

• commented on Dec. 18, 2015, 10:54 p.m.

It's fixed now; these issues occur sometimes when we update the judges.