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快速排序: ra4$/@3n
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package org.rut.util.algorithm.support; iE;D_m.>`O
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import org.rut.util.algorithm.SortUtil; yK3b^
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/** RMfKM!
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* @author treeroot )=vQrMyB
* @since 2006-2-2
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* @version 1.0 O^+H:Y|
*/ x]=s/+Y
public class QuickSort implements SortUtil.Sort{ 7ZsBYP8%
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/* (non-Javadoc) 7i$)iNW
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 7|/Ct;oO:
*/ $yA>j (k4
public void sort(int[] data) { Q*J8`J:#^R
quickSort(data,0,data.length-1); ~5Cid)Q}@o
} :p@.aD5
private void quickSort(int[] data,int i,int j){ &Oih#I
int pivotIndex=(i+j)/2; /#C}1emK
//swap dpPu&m+
SortUtil.swap(data,pivotIndex,j); ZHWxU
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int k=partition(data,i-1,j,data[j]); oXxY$x*R1
SortUtil.swap(data,k,j); \[57Dmo
if((k-i)>1) quickSort(data,i,k-1); ls928
if((j-k)>1) quickSort(data,k+1,j); |v6kZ0B<
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} aA|<W
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/** ~.*G%TW &V
* @param data .a0]1IkatV
* @param i P,}cH;w6Ck
* @param j fUg<+|v*
* @return `v|w&ty*
*/ 0S%xm'|N
private int partition(int[] data, int l, int r,int pivot) { l
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do{ $:i%\7=
while(data[++l] while((r!=0)&&data[--r]>pivot); [K=M;$iQ
SortUtil.swap(data,l,r); a^ __Z3g,
} :Q=tGj\G
while(l SortUtil.swap(data,l,r); -*<4 hFb
return l; T|%pvTIe
} b 5u8j
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} WE*L=_zDS
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改进后的快速排序: xRI7_8Jpyn
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package org.rut.util.algorithm.support; C;UqLMrOI
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import org.rut.util.algorithm.SortUtil; 0eP ]
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/** #aeKK7[
* @author treeroot s.#%hPX{
* @since 2006-2-2 |}-bMQ|
* @version 1.0 >STAPrBp+
*/ 5p}ri,Y<
public class ImprovedQuickSort implements SortUtil.Sort { ,dR<O.{0
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private static int MAX_STACK_SIZE=4096; I0qSx{K
private static int THRESHOLD=10; Tx19\\r
/* (non-Javadoc) ;K$ !c5
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) Mxmo}tt
*/ ev'` K=n8
public void sort(int[] data) { VK]cZ%)
int[] stack=new int[MAX_STACK_SIZE]; 5{"v/nXV
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int top=-1; wqnHaWd*
int pivot; ^c-8~r|y,
int pivotIndex,l,r; <l.l6okp
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stack[++top]=0; ms]r1x"
stack[++top]=data.length-1; 6/5Xy69:h
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while(top>0){ cEK<CV
int j=stack[top--]; `B A'a" $
int i=stack[top--]; #B!HPlrv
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pivotIndex=(i+j)/2; rsaN<6#_^Q
pivot=data[pivotIndex]; sy]hMGH:3W
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SortUtil.swap(data,pivotIndex,j);
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//partition zzH^xxg
l=i-1; m}$7d5
r=j; lZr}F.7
do{ w!eY)p<
while(data[++l] while((r!=0)&&(data[--r]>pivot)); hE;|VSdo
SortUtil.swap(data,l,r); cp)BPg
} T2ZB(B D
while(l SortUtil.swap(data,l,r); Dx5X6 t9=
SortUtil.swap(data,l,j); +e87/\5
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if((l-i)>THRESHOLD){ dHsI<