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快速排序: F/D/1w^ iR
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package org.rut.util.algorithm.support; xGX U7w:X
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import org.rut.util.algorithm.SortUtil; cA`X(Am6]g
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/** !r+SE
* @author treeroot }do=lm?/
* @since 2006-2-2 6Ou[t6
* @version 1.0 M_\)<a(8
*/ Xyw;Nh!!d
public class QuickSort implements SortUtil.Sort{ )(`,!s,8)
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/* (non-Javadoc) w5mSoKb
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) ( z.\,M
*/ Yd<q4VJR
public void sort(int[] data) { SY+$8^
quickSort(data,0,data.length-1); xx,|n
} L%4Do*V&
private void quickSort(int[] data,int i,int j){ Mj:=$}rs^
int pivotIndex=(i+j)/2; {c=H#- A
//swap &fwb?Vn4
SortUtil.swap(data,pivotIndex,j); u]t#Vf-$u
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int k=partition(data,i-1,j,data[j]); )n$RHt+:>
SortUtil.swap(data,k,j); T28Q(\C:}
if((k-i)>1) quickSort(data,i,k-1); C?PgC~y)
if((j-k)>1) quickSort(data,k+1,j); +p &$`(
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} Ga$EM
/** @ {8xL
* @param data v ce1'aW
* @param i 3HB(rTw
* @param j
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* @return W$u/tRF
*/ 3?yq*uE}
private int partition(int[] data, int l, int r,int pivot) { .KE2sodq
do{ c +]5[6
while(data[++l] while((r!=0)&&data[--r]>pivot); +q)B4A'J!
SortUtil.swap(data,l,r); 'M3V#5l)@|
} SWMi+)
while(l SortUtil.swap(data,l,r); qISzn04
return l; ?r(Bu
} wfBf&Z0{
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} N`!=z++G
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改进后的快速排序: "\x\P)j0>
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package org.rut.util.algorithm.support; PD@@4@^
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import org.rut.util.algorithm.SortUtil; *qL"&h5W
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/** !$.h[z^
* @author treeroot n ,CMGe^:
* @since 2006-2-2 |PW.CV0,
* @version 1.0 <Z9N}wY,8
*/ M9dUo7
public class ImprovedQuickSort implements SortUtil.Sort { |%7OI#t^
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private static int MAX_STACK_SIZE=4096; YDo,9
private static int THRESHOLD=10; #wZBWTj.
/* (non-Javadoc) J l9w/T
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) p+|(lrYC
*/ jRo4+8
public void sort(int[] data) { xouy|Nn'
int[] stack=new int[MAX_STACK_SIZE]; <LOas$
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int top=-1; }TAHVcX*p
int pivot; K@+(6\6I
int pivotIndex,l,r; rJ_fg$.<
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stack[++top]=0; 'Lv>!s 7
stack[++top]=data.length-1; "r.eN_d
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while(top>0){ nXcOFU
int j=stack[top--]; d"JI4)%
int i=stack[top--]; P*sb@y>}O
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pivotIndex=(i+j)/2; tD !$!\`O
pivot=data[pivotIndex]; ]h0 K*{
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SortUtil.swap(data,pivotIndex,j); $4*k=+wS
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//partition 4?9cyv4H
l=i-1; 4+_r0
r=j; }@S''AA\
do{ :6X?EbXhK
while(data[++l] while((r!=0)&&(data[--r]>pivot)); L
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SortUtil.swap(data,l,r); 0'.7dzz
} YkbZ 2J*-
while(l SortUtil.swap(data,l,r); (xhV>hsA
SortUtil.swap(data,l,j); dGBVkb4]T
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if((l-i)>THRESHOLD){ 7e
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stack[++top]=i; 9a0ibN6m
stack[++top]=l-1; d 1bx5U
} dTW3mF4=
if((j-l)>THRESHOLD){ q2KWSh5
stack[++top]=l+1; $mp'/]
stack[++top]=j; Ik74%x7G`
} orzy&4
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} X[up$<