归并排序: +x{o
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package org.rut.util.algorithm.support; vfn[&WN]
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import org.rut.util.algorithm.SortUtil; 5uG^`H@X
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/** {Zv%DV4_$
* @author treeroot a$?d_BX
* @since 2006-2-2 z\<,}x}V
* @version 1.0 ma-GvWD2
*/ s@&3;{F6D
public class MergeSort implements SortUtil.Sort{ VDOC>
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/* (non-Javadoc) tvf.K+
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) wz3X;1l`c
*/ Jc?zX8>Ae:
public void sort(int[] data) { G~C-tAB
int[] temp=new int[data.length]; 5\zR>Tg".
mergeSort(data,temp,0,data.length-1); HD#>K 7
} ;39a`
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private void mergeSort(int[] data,int[] temp,int l,int r){ 0kCo0{+n
int mid=(l+r)/2; *=B<S/0
if(l==r) return ; e.L&A|
mergeSort(data,temp,l,mid); 4Ia'Yr
mergeSort(data,temp,mid+1,r); ,<+:xl
for(int i=l;i<=r;i++){ }l+_KA
temp=data; |LJv*
} @TW:6v`
int i1=l; v&G9HiH
int i2=mid+1; ,&3+w~Ua
for(int cur=l;cur<=r;cur++){ ,7cw%mQA
if(i1==mid+1) Zs t)S(
data[cur]=temp[i2++]; l'[;q '
else if(i2>r) cQLPgE0
data[cur]=temp[i1++]; ~pp<
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else if(temp[i1] data[cur]=temp[i1++]; q&[G^9
else i[LnU#+
data[cur]=temp[i2++]; yuC$S&Y>!
} >0:3CpO*
} O[$X36z
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改进后的归并排序: #tUhul/O
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package org.rut.util.algorithm.support; `qd5+~c
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import org.rut.util.algorithm.SortUtil; .<%q9Jy#
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/** F$4=7Njv
* @author treeroot h&i(Kfv*
* @since 2006-2-2 q1YNp`]0i8
* @version 1.0 +%[,
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*/ *`qI<]!
public class ImprovedMergeSort implements SortUtil.Sort { w(_:+-rqQ<
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private static final int THRESHOLD = 10; p`&{NR3+
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/* c8]%,26.
* (non-Javadoc) h*KDZ+{)
* A #SO}c
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[])
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*/ 9wc\~5{li
public void sort(int[] data) { =>>Dnp
int[] temp=new int[data.length]; f#AuZ]h
mergeSort(data,temp,0,data.length-1); :T PG~`k(
} SF:{PgGMi
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private void mergeSort(int[] data, int[] temp, int l, int r) { 7}\AhQ, S
int i, j, k; [-#1;!k
int mid = (l + r) / 2; OY|9V
if (l == r) )40YA\V
return; IeChz d
if ((mid - l) >= THRESHOLD) 9`/ywt3Y
mergeSort(data, temp, l, mid); ;7E"@b,tPN
else G,Yctv
insertSort(data, l, mid - l + 1); t:lDFv4s
if ((r - mid) > THRESHOLD) QHje}
mergeSort(data, temp, mid + 1, r); $B>L_~cS
else .AX%6+o
insertSort(data, mid + 1, r - mid); 8KP
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for (i = l; i <= mid; i++) { D5@}L$u
temp = data; |@b|Q,
} c
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for (j = 1; j <= r - mid; j++) { ML$#&Z@
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temp[r - j + 1] = data[j + mid]; j&.JAQ*2;
} Tf$> ^L
int a = temp[l]; /L$q8 +
int b = temp[r]; 3- d"-'k
for (i = l, j = r, k = l; k <= r; k++) { R(y`dQy<K
if (a < b) { nx`W!|g$`
data[k] = temp[i++]; lr)MySsu#H
a = temp; <.lN'i;(
} else { y&4im;X0
data[k] = temp[j--]; 70*yx?T V
b = temp[j]; gQ '=mU
} ?OO !M
} `ALQSo~l
} u0+<[Ia'q
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/** T3)m{gv0`
* @param data `+KLE(]vyH
* @param l U!"RfRD.<
* @param i S)2 U oj
*/ hZe9 Y?)
private void insertSort(int[] data, int start, int len) { 3\<(!yY8
for(int i=start+1;i for(int j=i;(j>start) && data[j] SortUtil.swap(data,j,j-1); )086u8w )y
} RC"xnnIJv
} S=w ~bz,/
} *0a7H$iQ(]
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}