归并排序: Y"dTm;&
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package org.rut.util.algorithm.support; RG/P]
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import org.rut.util.algorithm.SortUtil; <!X]$kvG
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/** OQDx82E
* @author treeroot fL gHQ
* @since 2006-2-2 YT@N$kOg_
* @version 1.0 dhuIVBp!!e
*/ uuy0fQQ8ti
public class MergeSort implements SortUtil.Sort{ Iapzh y2l
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/* (non-Javadoc) wHQYBYKcd
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) z] |Y
*/ qLB(Th\&'
public void sort(int[] data) { 'NnmLM(oh
int[] temp=new int[data.length]; t'C9;
mergeSort(data,temp,0,data.length-1); N9z!-y'X
}
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private void mergeSort(int[] data,int[] temp,int l,int r){ 1+-F3ROP
int mid=(l+r)/2; l%`~aVGJ
if(l==r) return ; |~=4ZrcCP
mergeSort(data,temp,l,mid); -Q1~lN m:
mergeSort(data,temp,mid+1,r); b+BX >$
for(int i=l;i<=r;i++){ 0%3T'N%
temp=data; C+gu'hD
} 1i Q(q\%
int i1=l; |D8c=c%
int i2=mid+1; g$8aB{)
for(int cur=l;cur<=r;cur++){ 8)J,jh9q
if(i1==mid+1) "||G`%aO+t
data[cur]=temp[i2++]; Z3iX^
else if(i2>r) RP wP4Z
data[cur]=temp[i1++]; X<H+Z2d
else if(temp[i1] data[cur]=temp[i1++]; m h|HEkM
else fJY
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data[cur]=temp[i2++]; >*}m.'u
} dw7h@9\y
} k59.O~0V
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} [wJl]i
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改进后的归并排序:
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package org.rut.util.algorithm.support; C}]rx{xC
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import org.rut.util.algorithm.SortUtil; ;giT[KK
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/** td2bL4
* @author treeroot q -^Z=,<
* @since 2006-2-2 }5"19
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* @version 1.0 DzY`O@D[
*/ s06R~P4
public class ImprovedMergeSort implements SortUtil.Sort { d.NB@[?*
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private static final int THRESHOLD = 10; ~|e H8@o
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/* f=40_5a6
* (non-Javadoc) J_XbtCmt
* kC+dQ&@g{
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) v=+> ids
*/ YZp]vlm~
public void sort(int[] data) { \JZ'^P$Q
int[] temp=new int[data.length]; $EuI2.o
mergeSort(data,temp,0,data.length-1); y#e<]5I
} O[&G6+
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private void mergeSort(int[] data, int[] temp, int l, int r) { q.RW_t~
int i, j, k; C6,W7M[c
int mid = (l + r) / 2; 1Q9eS&
if (l == r) 79MB_Is]s
return; 7ZgFCK,8m,
if ((mid - l) >= THRESHOLD) z^9df(
mergeSort(data, temp, l, mid); bC]GL$ph9*
else FDRpK5cw
insertSort(data, l, mid - l + 1); #'kVW{
if ((r - mid) > THRESHOLD) I*8_5?)g<
mergeSort(data, temp, mid + 1, r); a~[]Ye@H
else Jm
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insertSort(data, mid + 1, r - mid); u|E9X[%
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for (i = l; i <= mid; i++) { m2Q#ATLW
temp = data; ,vUMy&AV
} ed7Hz#Qc
for (j = 1; j <= r - mid; j++) { qL68/7:A
temp[r - j + 1] = data[j + mid]; N/mC,7Q
} -o0~xspF
int a = temp[l]; {-\VX2:;[9
int b = temp[r]; )`]} D[j
for (i = l, j = r, k = l; k <= r; k++) { TWgI-xB
if (a < b) { "@E(}z'sM
data[k] = temp[i++]; 81U(*6
a = temp; :. a}pgh
} else { 1:lhZFZ
data[k] = temp[j--]; _ ;_NM5
b = temp[j]; s&zg!~@5b
} cwA+?:Ry}
}
fj])
}
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/** &`[Dl(W
* @param data c1p*}T
* @param l Wtwh.\Jba
* @param i |7l*
*/ t6O/Q0_
private void insertSort(int[] data, int start, int len) { AW:WDNQh8n
for(int i=start+1;i for(int j=i;(j>start) && data[j] SortUtil.swap(data,j,j-1); mEe JK3D[
} "5R8Zl+
} %8yX6`lH
} l %{$CmG\
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}