OLOLO - Onotole needs your help

Onotole has a lot of pyani. Each pyani has a number, writing on it. Pyanis with equal numbers are indistinguishable. Onotole knows everything, so, he knows that each pyani appeared twice, and only one pyani is unique. He wants to get вздръжни эффект, and he needs the unique pyani. Given the list of pyanis denote which one of them appeared once (it is guaranteed that other pyanis appeared twice).


First line of input contains number of pyanis N <= 500 000. Next N lines contain a single positive integer 1 <= Pi <= 10^9.


Output one positive integer on pyani, which appeared once.



Output: 8

Onotole has found not optimal AC algorithms, so all solutions will be rejudged. He is watching you.

hide comments
smtcoder: 2016-08-21 11:32:27

Really a very good concept in this question..looks like a very very easy problem but time limit forces you to use that concept..learnt something new from it :)

ankit1cool: 2016-08-21 08:53:06

good question learnt a new concept

madhavgaba: 2016-08-20 16:00:23

Tutorial worthy ques... AC in one go

Last edit: 2016-08-20 16:00:48
sayedathar11: 2016-08-19 03:43:19

The time constraints of the problem makes it special other wise it is very trivial problem needed 2 attempts for That :)

pratyush2311: 2016-08-04 17:26:46

c++ users,use scanf and printf instead of cin and cout respectively.

vaibhavahuja: 2016-07-31 03:24:24

TLE every time in python. no matter what i use.

syed_omar_ali_: 2016-07-11 16:17:46

Easy One! My 50th. Happy Coding!

iharsh234: 2016-07-01 10:57:06

can you check your input file please,Is there a blank line between two number?

suraj: 2016-06-15 00:14:00

use scanf

ianand: 2016-05-27 16:28:17

Use fast IO for java

Added by:Efim
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64