ACM??????????? ACM International Collegiate Programming Contest (ACM-ICPC)

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ACM???????????ACM International Collegiate
Programming Contest(ACM-ICPC)
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ACM-ICPC

• ???????????????
• ????Baylor University,?????(Association for
  Computing Machinery, ACM) ?IBM????

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ICPC??Battle of the Brains

• ???????????????
• ????????,????????,?????????????,??????????????????
  ,??????????
• ??????????????????,?????????????

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??

• ???1970????????AM???????????????the Alpha
  Chapter of the UPE Computer Science Honor
  Society?
• ??,??????????????,?1977??ACM????????
• ?1997?IBM????????,?????????

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Contest Rule

• ICPC ??????
• ??? (Regional Contest)
• ??? (World Final)
• ?????????????????,??????????
• ?????????????????,??????????????

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Contest Rule

• ?????????????,???3??????
• ?????????????(????????),??????2???????4???????
• ????1????5??????C?C?Java?Pascal??????8?10???,???
  ?????????????????

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Contest Rule

• ?????????????????????????
• ??????????????????20??penalty?

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Contest Rule

• ???????????????????,??????????????,????? accepted
  (??) ? wrong answer (??),???????????????????
• ????
• Accepted
• Accepted (P.E.)
• Wrong Answer
• Time Limit Exceeded
• etc

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Error Messages

• Accepted ???????????????,????????????.
• Aceepted (P.E.) (Presentation Error)????Accepted,
  ??????????,????????? (???????,???????).
• Wrong Answer???????????,????????????.
• Time Limit Exceeded (TL)??? Judge
  ????????,?????????????????.
• Memory Limit Exceeded (ML) ?????????????.
• Output Limit Exceeded (OL)???????,????.

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Error Messages

• Compile Error (CE)????
• Submission Error (SE)??,???ID,???????,??????????
• Runtime Error(SIGSEGV)??????,????????,??????????,
  ??????0,???????????(?????????????)
• Restricted Function (RF)???????????????(?????),?s
  ystem (...)

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Contest Rule

• ??A?B???????????
• A???????100?245????
• A??????100245345
• B???????120?200????,?B???????2?(????)?
• B?????120200020340
• B??????????

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??????

• ????????????????????,??????????
• ????? ACM ??????????????????,?????? ACM
  ????????????????,??????????
• ??????????????? ACM ??????????????????????,???????
  ??????????????

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??????

• ?34 ?ACM ?????????????? ???
• 2009 the 34th Annual ACM International Collegiate
  Programming ContestAsia Regional Hsinchu Site
• ????????
• ??????
• 2009 ?10 ?3011?1 ?

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2010 Final

• The 34th ACM International Collegiate
  Programming Contest World Finals
• Harbin, China, February 1-6, 2010

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Tips

• ???Online Judge?????
• Universidad de Valladolid Online Judge
• Ural State University Online Judge
• Tianjin University Online Judge
• Saratov State University Online Judge
• Sphere Online Judge
• ACM-ICPC Live Archive Around the World
• MIPT Online Judge
• Peking University Online Judge
• Zhejiang University Online Judge
• Harbin Institute of Technology Online Judge
• Fuzhou University Online Judge
• Online Problems Solving System

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Tips

• ????????
• ????????????? GNU/Linux SUSE Enterprise for
  desktop 10
• World Final????????Fedora Core 4 Linux
• ???????????????
• ??????????? GNU C/C ?????? Eclipse
• World Final?????? Java (version 1.5)?C/C (GCC
  4.0)? Pascal ?????? Java - Eclipse 3.1?C/C -
  CDT 3.0 under Eclipse 3.1?Pascal - Borland Kylix
  Version 3.0
• ??????????
• PC2 (Programming Contest Control System)

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Tips

• ??????
• ????????????
• ??????
• ??????
• ?????????,????????,???????
• ??????????????,???????????????
• ????
• ?????????????????????????????????????,????????????
  ????????????PDA,?????????????,???????????
• ??????????

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Tips

• ???(??)?????????C Standard Template Library
• E.G.include ltstl.hgtstackltintgt Squeueltchargt
  Qpriority_queueltintgt PQ
• stack - S.push(), S.top(), S.pop(), S.empty()
• You should always top on pop because top returns
  but does not remove the element on top, while pop
  removes but does not return the element.
• Linked implementations ensure the stack will
  never be full.
• queue Q.front(), Q.back(), Q.push(), Q.pop(),
  and Q.empty()
• hash_map H.erase(), H.find(), H.insert()
• priority_queue PQ.push(), PQ.top(), PQ.pop(),
  PQ.empty()
• set S.set_union, S.set_intersection
• sort or stable_sort

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ACM 10041

• Vitos family

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??

• Background 
• The world-known gangster Vito Deadstone is moving
  to New York. He has a very big family there, all
  of them living in Lamafia Avenue. Since he will
  visit all his relatives very often, he is trying
  to find a house close to them.
• Problem 
• Vito wants to minimize the total distance to all
  of them and has blackmailed you to write a
  program that solves his problem.

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Input output

• Input 
• The input consists of several test cases. The
  first line contains the number of test cases. For
  each test case you will be given the integer
  number of relatives r ( 0 lt r lt 500) and the
  street numbers (also integers) where they live
  ( 0 lt si lt 30000 ). Note that several relatives
  could live in the same street number.
• Output 
• For each test case your program must write the
  minimal sum of distances from the optimal Vito's
  house to each one of his relatives. The distance
  between two street numbers si and sj is dij
  si-sj.

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????

• ????? Ai i 0.n
• ?? k, ?? ????
• ??????

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Sample input output

• Sample Input 
• 2 2 2 4 3 2 4 6
• Sample Output 
• 2 4

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????

• ????????(median),???????????

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??Java???

• import java.util.
• class Vito
• static int ??new int500
• static Scanner ?? new Scanner(System.in)
• public static void main(String ??)
• int ??? ??.nextInt()
• for(int i1ilt???i)
• System.out.println(?????????())
• //??main() ??????
• static long ?????????()
• long ???0
• int ????
• int ?? ??.nextInt()
• for (int i0ilt??i)
• ??i ??.nextInt()

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??Java???

• for (int i??-1igt1--i)
• for (int j0jlti-1 j)
• if(??jgt??j1)
• int t??j
• ??j??j1
• ??j1t
• ????????/2
• for (int i0ilt??i)
• ???Math.abs(??i-????)
• return ???
• //???????????() ??????
• //??Vito ??????

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Java???

• import java.util.Scanner
• /When you submit your program to UVa Judge, you
  have to change the class name to be Main. And use
  only variables in English. Or you will get
  compilation error /
• class Vito2 //change the calss name to be Main.
  Or you will get runtime error
• static int Addressnew int500
• static Scanner input new Scanner(System.in)
• public static void main(String args)
• int cases input.nextInt()
• for(int i1iltcasesi)
• System.out.println(process())
• //??main() ??????
• static long process()
• long totalD0
• int bestAddress
• int people input.nextInt()
• for (int i0iltpeoplei)
• Addressi input.nextInt()
• for (int ipeople-1igt1--i)
• for (int j0jlti-1 j)
• if(AddressjgtAddressj1)

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Java???

• for (int ipeople-1igt1--i)
• for (int j0jlti-1 j)
• if(AddressjgtAddressj1)
• int tAddressj
• AddressjAddressj1
• Addressj1t
• bestAddressAddresspeople/2
• for (int i0iltpeoplei)
• totalDMath.abs(Addressi-bestAddress)
  
• return totalD
• //??process() ??????
• //??Vito2 ??????

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C???

• include "iostream.h"
• include "math.h"
• int door500
• long int process()
• int main()
• int cases
• cingtgtcases
• for(int i1iltcasesi)
• coutltltprocess()ltltendl
• return 0
• //??main() ??????
• long int process()
• long int total0
• int best
• int people
• cingtgtpeople
• for (int i0iltpeoplei)
• cingtgtdoori
• for (int ipeople-1igt1--i)

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C???

• for (int ipeople-1igt1--i)
• for (int j0jlti-1 j)
• if(doorjgtdoorj1)
• int tdoorj
• doorjdoorj1
• doorj1t
• bestdoorpeople/2
• for (int i0iltpeoplei)
• total(long int)fabs(doori-best)
• return total
• //??process() ??????