归并排序: heD,&OX
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package org.rut.util.algorithm.support; q"aPJ0ni'
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import org.rut.util.algorithm.SortUtil; ,J9}.}Hd
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/** r25Z`X Z
* @author treeroot m =&j@
* @since 2006-2-2 (N U0Tw
* @version 1.0 M$CVQ>op:
*/ Q2~5"
public class MergeSort implements SortUtil.Sort{ >BqCkyM9Kf
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/* (non-Javadoc) )}X5u%woV
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) gAE!aKy
*/ kC^.4n
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public void sort(int[] data) { StQ@g
int[] temp=new int[data.length]; rH}fLu8,;Q
mergeSort(data,temp,0,data.length-1); C%H9[%k
} oK-!(1A-
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private void mergeSort(int[] data,int[] temp,int l,int r){ E5x]zXy4
int mid=(l+r)/2; .1ddv4Hk
if(l==r) return ; >,g5Hkmqr
mergeSort(data,temp,l,mid); N
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mergeSort(data,temp,mid+1,r); :Z2tig nL
for(int i=l;i<=r;i++){ YQ,tt<CQ
temp=data; By)3*<5a_
} ]O@"\_}
int i1=l; Xm[Czd]%
int i2=mid+1; $U'3MEEw
for(int cur=l;cur<=r;cur++){ R+.
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if(i1==mid+1) }V^e7d
data[cur]=temp[i2++]; WV_`1hZX
else if(i2>r) 52<~K
data[cur]=temp[i1++]; {^&k!H2
else if(temp[i1] data[cur]=temp[i1++]; ;mJkqbVol
else 8gpB z'/,
data[cur]=temp[i2++]; Tt6{WDscZ
} r>3^kL5UI
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} b:B[3|
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改进后的归并排序: U1^l+G^,~
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package org.rut.util.algorithm.support; !`C?nY
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import org.rut.util.algorithm.SortUtil; iB{xvyR
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/** $HRed|*.C
* @author treeroot )q(:eoLDm
* @since 2006-2-2 (@?eLJlT
* @version 1.0 U?6yke
*/ ^uBwj}6
public class ImprovedMergeSort implements SortUtil.Sort { (n=Aa;
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private static final int THRESHOLD = 10; @W [{2d
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/* 97x%2.\:
* (non-Javadoc) ;tN4HiN
* [`bZ5*&
* @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) *SGlqR['\e
*/ D{svR-~T
public void sort(int[] data) { eYDgEM
int[] temp=new int[data.length]; 0 0,9azs
mergeSort(data,temp,0,data.length-1); 5&|5 a} 8
} NTVHnSoHh
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private void mergeSort(int[] data, int[] temp, int l, int r) { V* Qe5j9
int i, j, k; $F1_^A[
int mid = (l + r) / 2; 3B"7VBK{
if (l == r) As}eUm)B5c
return; u[mY!(>nQ
if ((mid - l) >= THRESHOLD) Gy^FrF
mergeSort(data, temp, l, mid); g =x"cs/[
else z"av|(?d
insertSort(data, l, mid - l + 1); d
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if ((r - mid) > THRESHOLD) =jG?v'X
mergeSort(data, temp, mid + 1, r); G:hU{S7
else a],h<wGEx
insertSort(data, mid + 1, r - mid); d"!yD/RD
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for (i = l; i <= mid; i++) { Ge~,[If+
temp = data; |Pf(J;'[
} D@5s8xv
for (j = 1; j <= r - mid; j++) { M4H"].Zm
temp[r - j + 1] = data[j + mid]; i?W]*V~ply
} .S6ji~;r
int a = temp[l]; CjmV+%b4
int b = temp[r]; 8qmknJC
for (i = l, j = r, k = l; k <= r; k++) { rV U:VL`2
if (a < b) { pDmK
data[k] = temp[i++]; l<n5gfJ
a = temp; 1 Xa+%n9
} else { Zr9 d&|$
data[k] = temp[j--]; W1<