EKO - Eko

Lumberjack Mirko needs to chop down M metres of wood. It is an easy job for him since he has a nifty new woodcutting machine that can take down forests like wildfire. However, Mirko is only allowed to cut a single row of trees.

Mirko‟s machine works as follows: Mirko sets a height parameter H (in metres), and the machine raises a giant sawblade to that height and cuts off all tree parts higher than H (of course, trees not higher than H meters remain intact). Mirko then takes the parts that were cut off. For example, if the tree row contains trees with heights of 20, 15, 10, and 17 metres, and Mirko raises his sawblade to 15 metres, the remaining tree heights after cutting will be 15, 15, 10, and 15 metres, respectively, while Mirko will take 5 metres off the first tree and 2 metres off the fourth tree (7 metres of wood in total).

Mirko is ecologically minded, so he doesn‟t want to cut off more wood than necessary. That‟s why he wants to set his sawblade as high as possible. Help Mirko find the maximum integer height of the sawblade that still allows him to cut off at least M metres of wood.


The first line of input contains two space-separated positive integers, N (the number of trees, 1 ≤ N ≤ 1 000 000) and M (Mirko‟s required wood amount, 1 ≤ M ≤ 2 000 000 000).

The second line of input contains N space-separated positive integers less than 1 000 000 000, the heights of each tree (in metres). The sum of all heights will exceed M, thus Mirko will always be able to obtain the required amount of wood.


The first and only line of output must contain the required height setting.


4 7
20 15 10 17

5 20
4 42 40 26 46


hide comments
ternion1121: 2023-07-14 19:33:36

I am using long long data type, yet the master judge test case fails. May I get guidance on how I can know my mistake?

daddywithmommy: 2023-07-09 09:58:59

Hi guys , so I have used long long int every where yet it getting wrong answer at test case 9 , how do i fix ?

sushilsuthar: 2023-05-31 09:48:14

If the master judge is failing, make sure you have used long long int since 1 ≤ N ≤ 1 000 000 and 1 ≤ M ≤ 2 000 000 000.

charandeep: 2023-03-30 23:33:02


deathmonarch: 2023-03-23 15:46:31

can solve in o(n) using prefix sum. No need of binary search; Use math + prefixsum;

Last edit: 2023-03-26 10:32:18
chain_staker: 2023-03-15 12:50:08

Even after making long long almost all variables it does not pass the master judge. <snip> if someone has the patience to look at it.

[Simes]: this is not the place for debugging code, use the forum.

Last edit: 2023-03-15 14:22:47
ajit_kun: 2023-01-11 18:47:02

must use 'long long' instead of using 'int' otherwise it will not be accepted .

priyanshu3343: 2022-10-17 05:49:00

please help what is wrong in this code
[Simes]: use the forum for this.

Last edit: 2022-10-17 07:34:43
code_begins: 2022-10-09 12:34:45

AC in one go..Good question..Don't forgot to use long long otherwise wrong answer

Last edit: 2022-10-09 12:38:50
priyanshu3343: 2022-10-06 07:18:25

what all the test cases used

Last edit: 2022-10-06 16:35:45

Added by:ghorvat
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Resource:COCI 2011/2012