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快速排序: lwY2zX&%)/
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package org.rut.util.algorithm.support; .?C-J
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import org.rut.util.algorithm.SortUtil; AD_aI
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/** *3,Kn}ik
* @author treeroot &W'X3!Te
* @since 2006-2-2 wOhiC$E46
* @version 1.0 }]i re2j8
*/ z?9vbx
public class QuickSort implements SortUtil.Sort{ ]z^*1^u^ig
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/* (non-Javadoc) $)V_oQSqn
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) v6Vd V.BI
*/ rKK{*%n
public void sort(int[] data) { 4P1<Zi+<
quickSort(data,0,data.length-1); 7'pmW,;
} s]D&):
private void quickSort(int[] data,int i,int j){ DH3.4EUWS
int pivotIndex=(i+j)/2; "4 Lt:o4x
//swap `i'72\(
SortUtil.swap(data,pivotIndex,j); D^R=
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int k=partition(data,i-1,j,data[j]); G4VdJ(_
SortUtil.swap(data,k,j); e:&+m `OSH
if((k-i)>1) quickSort(data,i,k-1); C(RZ09,.S
if((j-k)>1) quickSort(data,k+1,j); m1](f[$
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} R]s\s[B
/** o~
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* @param data dZMOgZ.!yr
* @param i I UMt^z
* @param j I04GQql
* @return R F)Qsa
*/ ]8Eci^i
private int partition(int[] data, int l, int r,int pivot) { *5kQ6#l
do{ VE
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while(data[++l] while((r!=0)&&data[--r]>pivot); @Lp;p$G`
SortUtil.swap(data,l,r); u]D>O$_ s
} fmDn1N-bG
while(l SortUtil.swap(data,l,r); BdK2I!mm
return l; PYOU=R%o`8
} pl-2O $
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} 7tEK&+H`
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改进后的快速排序: >z(AQ
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package org.rut.util.algorithm.support; APfDy
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import org.rut.util.algorithm.SortUtil; )_MIUQ%
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/** W7j-siWJ
* @author treeroot [f_4%Now
* @since 2006-2-2 N33{vx
* @version 1.0 j K!Y-
*/ r`; "
public class ImprovedQuickSort implements SortUtil.Sort { v7V.,^6+
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private static int MAX_STACK_SIZE=4096; kLr6j-X
private static int THRESHOLD=10; -w0U}Te^
/* (non-Javadoc) gypE~@
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) QGWfF,q
*/ !<ae~#]3P
public void sort(int[] data) { M~6x&|2
int[] stack=new int[MAX_STACK_SIZE]; 7 Q`'1oE?
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int top=-1; !uC`7a
int pivot; &$'=SL(Z
int pivotIndex,l,r; [i8,rOa7
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stack[++top]=0; d1MVhE
stack[++top]=data.length-1; ]>K02SVT:
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while(top>0){ L$ nFRl&
int j=stack[top--]; vPVA^UPNV
int i=stack[top--]; ,P?R
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pivotIndex=(i+j)/2; :6,qp?/
pivot=data[pivotIndex]; 2EHeQ|#
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SortUtil.swap(data,pivotIndex,j); hhS]wM?B
7_AR()CM
//partition !kPZuU`T
l=i-1; -n C
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r=j; wU\3"!^h
do{ E!a5-SrR
while(data[++l] while((r!=0)&&(data[--r]>pivot)); 4_#yl9+
SortUtil.swap(data,l,r); <lx~/3<m
} qU'O4TWZ
while(l SortUtil.swap(data,l,r); /K#t$O4
SortUtil.swap(data,l,j); HxC_nh
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if((l-i)>THRESHOLD){ VTDp9s
stack[++top]=i; =Yxu {]G
stack[++top]=l-1; /r4QDwu
} (z[|\6O
if((j-l)>THRESHOLD){ nly`\0C
stack[++top]=l+1; ]"Do%<