http://ai.pku.edu.cn/cpp2010

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??????

• ???
• http//ai.pku.edu.cn/cpp2010

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???
2951 ???????? 2775 ????? 2787 ?24acm3278 catch
the cow Acm1321????
3
2951
????????? R ( 0.0 lt R lt 99.999 ) ,????????? R ?
n ???n ????? 0 lt n lt 25? ???????? R ? n? R ????
1 ? ? 6 ?, n ???? 8 ?? 9 ?? ????????,??????,?????
?? R ? n ???????????? 0 ??????? 0
????????,????????
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2951

• 95.123 12
• 0.4321 20
• 5.1234 15
• 6.7592 9
• 98.999 10
• 1.0100 12

548815620517731830194541.8990253434157159735359672
21869852721 .0000000514855464107695612199451127676
7154838481760200726351203835429763013462401 439920
25569.92857370126648804114665499331870370751166629
5476720493953024 29448126.764121021618164430206909
037173276672 90429072743629540498.1075960194566517
74561044010001 1.126825030131969720661201
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2951

• ???95.123 12??
• ???????? 3?
• ?????,????95.123 -gt 95123
• ?9512312 54881562051773183019454189902534341571
  5973535967221869852721
• ??????548815620517731830194541.8990253434157159735
  35967221869852721

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2951 ??

• includeltstdio.hgt
• includeltstring.hgt
• const int MAX100
• char s7
• int aMAX,e,p,b,be,en,i
• void mul()
• int i,w0
• for(i0iltMAXi)
• aiaibw
• wai/10
• aiai-w10

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• int main()
• while (scanf("s d",s,e)!EOF)
• memset(a,0,sizeof(a))
• b0 //Step 1 and Step 2
• for(i0iltstrlen(s)i)
• if (si'.') pstrlen(s)-i-1
• else bb10si-'0'
• a01 //Step 3
• for(i0iltei)
• mul()
• pe //Step 4
• for (beMAX-1abe0begtp-1be--)
• for (en0aen0enltpen)
• for (ibeigtpi--) printf("d",ai)
• if (enltp) printf(".")
• for (ip-1igteni--) printf("d",ai)
• printf("\n")

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2775 ?????
DATA SET 1 ROOT dir3 dir2
file1 file2
dir1 file1 file2 file3 file4 DATA SET
2 ROOT file1 file2

• file1
• file2
• dir3
• dir2
• file1
• file2
• file4
• dir1
• file3
• file2
• file1

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2775 ?????
??????????, ??????????????,???????????????????????
?. ???????????????????????????? ?????,?????????
?,?????,???????????,????,?????????,??????
file1 file2 dir3 dir2 file1 file2 file4 dir1
file3 file2 file1
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include ltiostreamgt include ltvectorgt include
ltstringgt include ltalgorithmgt using namespace
std void ListDir( const char root)
//????? int nCurLevel 0 //??????????? int
MyCompare( const void e1, const void
e2) //??????????? return strcmp( (const char
) e1, (const char ) e2)
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int main() int nDatasetNo 1 do cout
ltlt "DATA SET "ltlt nDatasetNo ltlt "" ltlt
endl nCurLevel 0 ListDir("ROOT")
//????? //???????test case char c do
//??????? c cin.peek() if( c '\r'
c '\n' ) cin.get() while( c '\r'
c '\n') if( c '') break else
cout ltlt endl nDatasetNo
while(1) return 0
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void ListDir( const char root) char
sLine200 char vFiles20030 int
nTotalFiles 0 int i,j for( i 0i lt
nCurLevel i ) cout ltlt " " cout ltlt
root ltlt endl do cin gtgt sLine switch(
sLine0 ) case '' case '' qsort(
vFiles, nTotalFiles,30,MyCompare) for( j 0
j lt nTotalFiles j ) for( i 0i lt
nCurLevel i ) cout ltlt "
" cout ltltvFilesj ltlt endl nCurLe
vel --//????????,????? return
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case 'f' strcpy( vFilesnTotalFiles
,sLine) break case 'd' nCurLevel
//????????,???? ListDir(
sLine) break while(1)
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2787 ?24

• ??
• 5 5 5 1
• 1 1 4 2
• 0 0 0 0
• ??
• YES
• NO

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2787 ?24

• ???k???24
• ???k???24,???k-1???24
• ???k????2??a?b,?????op?a?b?k?????,??(a op b)??

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include ltiostreamgt using namespace std double
Numbers5 bool Calc( double pNumbers, int n
) //?pNumbers????n???24????? int main() int
a4 int nZeroNum 0 while(true) for(
int i 0i lt 4i ) cin gtgt
Numbersi if( Numbersi 0 ) nZeroNum
if( nZeroNum 4 ) break if(
Calc( Numbers,4)) cout ltlt "YES"
ltltendl else cout ltlt "NO" ltlt
endl return 0
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bool Calc( double pNumbers, int n ) int
i,j,k double aNumber4 if( n 1 )
//?????????24,???????24,????? if( pNumbers0 gt
23.99999 pNumbers0 lt 24.00001 ) return
true else return false for( i 0i lt
n - 1i ) for( j i 1 j lt n j )
//??????? int m 0 for( k 0 k lt n k
) //??????? if( k ! i k ! j
) aNumberm pNumbersk //?????
?????,??????,???24 aNumberm pNumbersi
pNumbersj if( Calc( aNumber, n -1 ))
return true
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aNumberm pNumbersi pNumbersj if(
Calc( aNumber, n -1 )) return
true aNumberm pNumbersi -
pNumbersj if( Calc( aNumber, n -1
)) return true aNumberm pNumbersj -
pNumbersi if( Calc( aNumber, n -1
)) return true if( pNumbersi ! 0)
aNumberm pNumbersj /
pNumbersi if( Calc( aNumber, n -1
)) return true if( pNumbersj !
0) aNumberm pNumbersi /
pNumbersj if( Calc( aNumber, n -1
)) return true return false
//?????????,??????
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acm1321 ???? ??????????(?????????)??????,?????????
??????????????????????????,?????????????????,??k??
???????????C? Input ??????????? ??????????????,n
k,???????,???????nn????????,?????????? n lt 8 ,
k lt n ??-1 -1???????? ???n????????????n???,??
??????, . ??????(??????????????????)?
Output ???????,??????,?????????C (????Clt231)?
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acm1321 ???? Sample Input 2 1 . . 4 4 ...
... ... ... -1 -1 Sample Output 2 1
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acm1321 ???? ?? ????????,???????????????? ????
???????????????,??????????
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include ltiostreamgt using namespace std char
Grid99 int n,k int nTotal 0
//???? int anPos9 int nBlankRows 0
int nDoneNum 0 //???????? void Queen(int
nRow) int main() int i,j while( true)
cin gtgt n gtgt k if( n -1 k -1 )
break for( i 0i lt ni ) for( j
0j lt n j ) cin gtgt Gridij nTotal
0 nBlankRows 0 nDoneNum 0 Queen(0)
//??0???? cout ltlt nTotal ltlt endl return
0
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void Queen(int nRow) if( nRow n nDoneNum
k) //???????n?(???0??),???????????, //
?????,??????1 nTotal return int
i,j for( i -1 i lt n i )
//????????,????-1???????? if( i -1 )
if( nBlankRows lt n - k ) //??????? anPos
nRow -1//??? nBlankRows Queen(
nRow 1 ) //????????,?????????? nBlankRows
--
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else if( GridnRowi '' ) for(
j 0 j lt nRow j ) if( anPosj i )
//?????? break if( j nRow )
anPosnRow i //?nRow????i nDoneNum
//???????1 Queen(nRow 1
)//???? //????????,?????? //??? nD
oneNum --
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acm3278 Catch That Cow Farmer John has been
informed of the location of a fugitive cow and
wants to catch her immediately. He starts at a
point N (0 N 100,000) on a number line and
the cow is at a point K (0 K 100,000) on the
same number line. Farmer John has two modes of
transportation walking and teleporting.
Walking FJ can move from any point X to the
points X - 1 or X 1 in a single minute
Teleporting FJ can move from any point X to the
point 2 X in a single minute. If the cow,
unaware of its pursuit, does not move at all, how
long does it take for Farmer John to retrieve it?
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acm3278 Catch That Cow ?????? ??????,??RLE ?????
,??RLE ?? 1)????? xlt0??? 2)?????????,??????? 3
)??????,??????????,???????? ??????????????????,??
????????,??RLE
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include ltiostreamgt include ltstringgt include
ltmemorygt using namespace std int n,k struct
SNode int x int nSteps SNode
aQueue3000000 int anRepeated300000 int
nHead,nTail int main() cin gtgt n gtgt
k memset( anRepeated,0,sizeof(anRepeated)) nHe
ad 0 nTail 1 aQueue0.x
n aQueue0.nSteps 0
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while( nHead ! nTail ) if( aQueuenHead.x
k ) cout ltlt aQueuenHead.nSteps retur
n 0 if ( aQueuenTail.x lt k )
//????????,????????????? aQueuenTail.x
aQueuenHead.x 1 if( anRepeatedaQueuenTai
l.x 0 ) aQueuenTail.nSteps
aQueuenHead.nSteps 1 anRepeatedaQu
euenTail.x 1 nTail if(
aQueuenHead.x - 1 gt 0 ) aQueuenTail.x
aQueuenHead.x - 1 if( anRepeatedaQueuenTai
l.x 0 ) aQueuenTail.nSteps
aQueuenHead.nSteps 1 anRepeatedaQu
euenTail.x 1 nTail if(
aQueuenHead.x 2 - k lt k - aQueuenHead.x )
//?????????? aQueuenTail.x
aQueuenHead.x 2 if( anRepeatedaQueuenTai
l.x 0 ) aQueuenTail.nSteps
aQueuenHead.nSteps 1 anRepeatedaQueuenT
ail.x 1 nTail nHead

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if( aQueuenHead.x 2 - k lt k -
aQueuenHead.x ) //?????????? aQueuenTai
l.x aQueuenHead.x 2 if(
anRepeatedaQueuenTail.x 0 )
aQueuenTail.nSteps aQueuenHead.nS
teps 1 anRepeatedaQueuenTail.x
1 nTail nHead