DRCHEF - Editorial

editorial
, , , ,
39

can someone tell what those three testcases 6,7,9 could possibly look like, link to my solution here

40

Thanks for the shortened code but the result’s still the same. Am I missing something?

41

I did something very similar in the beginning and got all test cases correct but then next day went for a recheck and a test case was wrong and then I started overthinking on it …That is Sad…

42

Sorry i couldn’t understand there is some error with smallCountries values,

i ammended your code and got AC.
https://www.codechef.com/viewsolution/35618932

i did it little the way i actually did in contest.

43

thank you so much @anon52057084

44

hey even i got 6,7,9 wrong test cases, but for your test case i get answer as 4 can u check my solution here

45

Thank you for helping me out.

1 Like
46

This worked for me as well. But what were the test cases that we missed? OR Why did we add this 2*, i didn’t get it yet. Can you please tell the logic behind this **2 ** * p[i] >= x ?

48

Can someone tell me the answer of this test case?
1
2 4
7 14
The problem is accepting 3 as the answer whereas the answer should be 4.

  • If you give 4 cures in day 1, next day you can give only 6 cures because population becomes (7-4)*2=6. so in day 2 you can give 6 cures. On day 3, you can give 12 cures which is less than 14 so total 4 days is required. In no ways you can give all 7 cures in second day.
49

Try:
1
2 10
9 18
Ans: 2

50

On the day 2 you can send delivery man to 2nd country and can give 8 cures.

51

It means for second country you require 2 days because population is 14 so the answer is still 4

52

[CodeChef: Practical coding for everyone]
Can someone find error in my code. 2 test cases failing.Can somebody give me a failed test case…

53

A very simple solution:
https://www.codechef.com/viewsolution/35417013
see line number 22 to 47

Only 2 if conditions inside the for loop used to iterate sorted array.

54

WHY ll= x/2+x%2 ; why not ll=x ??

55

sorry i was wrong …my bad :sweat_smile:
on first day we send our delivery man to second country now we have 8 vaccine, ( 7 infected in country 1st and 14 infected in country 2nd) ,then on second day we send him to 1st country now we have 14 vaccine ( 0 infected in 1st country and 14 in 2nd country) , on third day we send him to cure 2nd country. I hope it’s clear now.

56

In subtask 2, it think it should be 2 * Ai >= x .

57

I presume you are asking if we can deliver to that country if 2*a_i=x. Yes, we can. We can deliver to that country while doubling x or at the end. Either way it accounts for only 1 day for that country. My algorithm choses to deliver at the end.

1 Like
58

I get you. Even I was thinking the same, I know many have done just hit and trail. I tried to get a proof and I submitted it assuming maximum population will always have enough people to be cured so that we can every time double supply for some country having less population.

@sudipandatta can you provide me some valid argument to prove ? :slight_smile: it’d be helpful

59

Thanks @rudraksh26