归并排序: }B_?7+
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package org.rut.util.algorithm.support; k(o(:-+x
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import org.rut.util.algorithm.SortUtil; uIBN
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/** 0!oqP1
* @author treeroot [w!T
* @since 2006-2-2 iiF`2
* @version 1.0 q" EW*k+
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*/ uQ|LkL%<^
public class MergeSort implements SortUtil.Sort{ Mdq|:^px
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/* (non-Javadoc) B):ZX#
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) mE_%
*/ *6eJmbFG
public void sort(int[] data) { Bh'!aip k
int[] temp=new int[data.length]; ]=9 d'WL
mergeSort(data,temp,0,data.length-1); L9XfR$7,z
} N;,zPW a
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private void mergeSort(int[] data,int[] temp,int l,int r){ )_\ ;l%&
int mid=(l+r)/2; W?"l6s
if(l==r) return ; ?XP4kjJ
mergeSort(data,temp,l,mid); D+BiclJ
mergeSort(data,temp,mid+1,r); ?|WoNA~j}`
for(int i=l;i<=r;i++){ 3Gr"YG{,
temp=data; $-u c#57
} %|ClYr
int i1=l; pL!,1D!
int i2=mid+1; <$K=3&:s8q
for(int cur=l;cur<=r;cur++){ !3iZa*
if(i1==mid+1) IaQm)"Z
data[cur]=temp[i2++]; ({@"{
else if(i2>r) 5D2mZ/
data[cur]=temp[i1++]; q*5L",
else if(temp[i1] data[cur]=temp[i1++]; 7VG*Wu
else m5&Ht (I%n
data[cur]=temp[i2++]; egBk7@Ko
} ,|A6l?iV
} W -HOl!)
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} :5$ErI
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改进后的归并排序: cvo+{u$s
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package org.rut.util.algorithm.support; )+|wrK:*v
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import org.rut.util.algorithm.SortUtil; B8?9L8M}
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/** xQU//kNL
* @author treeroot 4n@>gW
* @since 2006-2-2 j`q>YPp
* @version 1.0 DU8\1(
*/ .ahY 1CO
public class ImprovedMergeSort implements SortUtil.Sort { >N 2kWSa
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private static final int THRESHOLD = 10; #pgD-0_
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/* '
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* (non-Javadoc) _>]/. w2=
* Z.!<YfA)
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[])
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*/ 2O@ON/
public void sort(int[] data) { lR7;{zlSf'
int[] temp=new int[data.length]; Y:\]d1C
mergeSort(data,temp,0,data.length-1); O`1!&XT{x
} 8+dsTX`|S
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private void mergeSort(int[] data, int[] temp, int l, int r) { -^yc<%U
int i, j, k; fZr{x$]N0
int mid = (l + r) / 2; a%BC{XX
if (l == r) 3UW`Jyd`k
return; uL-kihV:-
if ((mid - l) >= THRESHOLD) &=*1[ j\
mergeSort(data, temp, l, mid); =,q/FY:
else lhJY]tQt/
insertSort(data, l, mid - l + 1); t#_6GL
if ((r - mid) > THRESHOLD) llR5qq=t
mergeSort(data, temp, mid + 1, r); )m3emMO2
else Q:7P
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insertSort(data, mid + 1, r - mid); V`LE 'E
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for (i = l; i <= mid; i++) { H)E,([
temp = data; g.Qn,l]X/p
} 6Iv};f"Y
for (j = 1; j <= r - mid; j++) { h lc!}{$%8
temp[r - j + 1] = data[j + mid]; c^'bf_~-W
} "~EAt$
int a = temp[l]; X]2Ib'(
int b = temp[r]; !KJ X$?
for (i = l, j = r, k = l; k <= r; k++) { ==?%]ZE8
if (a < b) { -6uLww=w4
data[k] = temp[i++]; 9<y{:{i
a = temp; l l*g *zt3
} else { +mD;\iW]
data[k] = temp[j--]; ~,};FI
b = temp[j]; yK"\~t[@X:
} Qi dI
} I4w``""c
} %%n&z6w