(Radix Sort)

1
????

• (Radix Sort)

2

• ??????????????????????,??????(Radix
  sort)?????????????????,????????

3
??

• ????????????????????????,???????????
• ??????????????k???,??????????n??????kn???????????
  ?
• ????????????,???????????,????????????????,??(nlogn
  )?????????????

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????
????
???
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?????
???
?????????????,??????????,???????(character
lists)????????????????????????????????????0?1??9?

6
?????
???
??????????????,??????????,??????????,?????2???????
???????????????????
7
????????? 015,56,107,228,312,371,452,456,575,71
4,749,833
?????,?????????????(???)?,??????????,?????9-8-3???
???????????,?????????
8
???

• ???gtC?????
• msd_sort(int a , int b , int l, int r, int
  factor)
• int i, j, v, count l , c l
• for ( i 0 i lt l i )
• count i 0
• for ( i l i lt r i )
• v a i / factor 10
• count v l

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• c 0 0
• for ( i 1 i lt l i )
• count i count i 1
• c i count i
• for ( i 1 i lt r i )
• j a i / factor 10
• b count j a i

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• for ( i 1 i lt r i )
• a i b i 1
• factor / 10
• for ( i 0 i lt 10 i )
• j c i l
• v ci l l 1
• if ( v gt j factor gt 0 )
• msd_sort( a, b, j, v, factor )

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• gt???????
• ?????????????
• ?????????????O(nlogr m),r???????????,m????
• ??????,??????O(n),???????,??(n n),n?????

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????-????

• include ltstudio.hgt
• void adjust ( int , int )
• int data 10 75, 23, 98, 44, 57, 12, 29, 64,
  38, 82
• void main ( )
• int i , j, k - 0, lst, temp 10 10

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• int order (10) 75,23,98,44,57,12,29,64,38,82
  
• printf ( \n ltlt Rp sort gtgt\n )
• printf ( Number )
• for ( i 0 i lt 10 i )
• printf ( d , data i )
• puts ( )
• for ( i 0 i lt 60, i ) printf ( -)
• while ( n lt 10 )

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• for ( i 0 i lt 10 i )
• lst ((data i / n ) 10 )
• temp lsd order lsd data i
• order lsd
• printf ( \nAccess )
• for ( i 1 i lt 10 i )
• for ( j 0 j lt order i j )
• data k temp i j
• printf ( d , data k )
• k

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• order i 0
• n 10
• k 0
• puts ( )
• for ( i 0 i lt 60 i ) printf ( - )
• printf ( \nSorting )
• for ( i 1 i lt 10 i )
• printf ( d , data i )

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?????

• External Sort

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

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??

• ????????????????,???????,?????????????????????????
  ????
• ?????????????runs),???????????????,???????????

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????????

• ???????
• ?????
• ?????
• ???
• ???????
• ????
• ?????????

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?????????
?? ??? ??? ???? ???? ???
?? ???? Bubble O(n2) O(n2) ???
?? ???? Insertion O(n2) O(n2) ??
?? ???? Selection O(n2) O(n2) ??
?? ???? Shell O(nlogn) O(ns)1ltSlt2 ???
?? ???? Quick O(nlogn) O(n2) ???
?? ???? Heap O(nlogn) O(nlogn) ???
?? ???? Binary tree O(nlogn) O(n2) ???
?? ???? Merge O(nlogn) O(nlogn) ??
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• ????????????.
• ????????????.
• ???????????????????????.?'?'????,?'??'?????.
• ????2?
• ????
• ???????????????.
• ????
• ?????????????????,?????????

22
?????

• ??????????????????O(N)
• ???????O(logN)
• ????????O(1)?

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???

• ????????????????????????,????????????
• ?????????,??N2?Nlog N??????
• ?????????????
• ????????
• ???????????