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.
Input
The first line of input contains two spaceseparated 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 spaceseparated 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.
Output
The first and only line of output must contain the required height setting.
Example
Input: 4 7 20 15 10 17 Output: 15
Input: 5 20 4 42 40 26 46 Output: 36
hide comments
mightyhelper:
20180208 19:31:11
I ran the test cases locally, and they gave the expected output, but Im getting WA, My program should work with up to 1000000 trees up to 1.8 * 10 ^ 13 mts high (I think thats acceptable : never seen a tree that tall) Last edit: 20180208 19:32:51 

spojabhi:
20171228 16:28:26
simple logic :) 

samvegt:
20171223 20:28:51
My solution took 0.70s ,still accepted, anyone knows why? 

avik26091998:
20171201 14:57:13
Nice Binary search problem!!! 

thanos_tapras:
20170924 21:57:14
AC in third attempt.


me_milan_11:
20170824 22:47:41
AC in one attempt :D


micro14:
20170813 10:14:06
My 50th :) 

nikhil2504:
20170719 20:40:29
In love with binary search XD


anurag_tangri:
20170702 16:36:07
AC IN ONE GO :) 

Sigma Kappa:
20170702 14:51:00
OK, this is a nice binary search problem. Got Accepted with nested binary searches. Now, my question is (unrelated to here) why say DP tag features "237" problems, but when I click on it it only shows ~4050 problems? Also, the sort feature doesn't work. Where should I write an email about these issues? 
Added by:  ghorvat 
Date:  20120702 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  COCI 2011/2012 