ABA12C - Buying Apples!

Harish went to a supermarket to buy exactly ‘k’ kilograms apples for his ‘n’ friends. The supermarket was really weird. The pricing of items was very different. He went to the Apples section and enquired about the prices. The salesman gave him a card in which he found that the prices of apples were not per kg. The apples were packed into covers, each containing ‘x’ kg of apples, x > 0 and ‘x’ is an integer. An ‘x’ kg packet would be valued at ‘y’ rupees. So, the placard contained a table with an entry ‘y’ denoting the price of an ‘x’ kg packet. If ‘y’ is -1 it means that the corresponding packet is not available. Now as apples are available only in packets, he decides to buy atmost ‘n’ packets for his ‘n’ friends i.e he will not buy more than n packets of apples.

Harish likes his friends a lot and so he does not want to disappoint his friends. So now, he will tell you how many friends he has and you have to tell him the minimum amount of money he has to spend for his friends.


The first line of input will contain the number of test cases, C.

Each test case will contain two lines.

The first line containing N and K, the number of friends he has and the amount of Apples in kilograms which he should buy.

The second line contains K space separated integers in which the ith integer specifies the price of a ‘i’kg apple packet. A value of -1 denotes that the corresponding packet is unavailable.

  • 0 < N <= 100
  • 0 < K <= 100
  • 0 < price <= 1000


The output for each test case should be a single line containing the minimum amount of money he has to spend for his friends. Print -1 if it is not possible for him to satisfy his friends.

Sample I/O

3 5
-1 -1 4 5 -1
5 5
1 2 3 4 5


Explanation of test cases:

1) As there are only 3 and 4kg packets in the shop, he will not be able to satisfy his friends as he would not be able to buy exactly 5kg of apples.

2) He can buy five 1kg packet as he has to buy 5 kg. So the min money he should spend is 5.

hide comments
saini428: 2016-01-24 22:17:31

my 60th,,,,,easy one

Amitayush Thakur: 2016-01-09 07:24:18

Input test file has spacing problem. My Java solution with BufferedReader didn't get accepted but when I changed it to scanner it got AC. Also the constraint on 'n' is not used. The language of the question is ambiguous too.

kejriwal: 2016-01-06 19:51:12

i think your testcases don't include the case where num of bags are > n !! cool problem though :) !!

naruto09: 2015-12-31 12:30:02

no use of varible "n"..but you can get AC even if you take n into account

Shubham Gupta: 2015-12-27 16:29:57

'n' is not taken into account while determining o/p.
3 4
1 3 -1 -1
Ac. O/p: 4 [he can take 4 packets of one kg,which is more than n]

Whereas, actual o/p should have been 5 [One packet of 2kg and two packets of 1kg each,which is equal to n].

Last edit: 2015-12-27 16:31:04
sneh sajal: 2015-12-25 20:34:33

note :- one item can be taken multiple times! good DP :)

priyank: 2015-12-14 10:10:12

nice question

vijay meena: 2015-12-05 18:39:53

same as Rod cutting. just change max into min thats it

munjal: 2015-10-29 18:57:43

Not at all good description of the question is provided ........ !!!!!!!!!!!!!!!!!!!!!!!!

LeppyR64: 2015-10-26 19:57:21

Regardless of everyone's complaining that the test cases do not exploit the fact that n is not considered, a solution that does consider that the number of pacakages is at most n will still get AC (Including mine). Please do mind the constraint that price can be equal to zero. O(k * n * k)

Added by:Kashyap Krishnakumar
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64
Resource:Own problem