(1)基本思想:在要排序的一组数中,假设前面(n-1)[n>=2] 个数已经是排
好顺序的,现在要把第n个数插到前面的有序数中,使得这n个数
也是排好顺序的。如此反复循环,直到全部排好顺序。
(2)实例
(3)用java实现
?class="java keyword">package
com.njue;?
?
public
class
insertSort {?
public
insertSort(){?
????
inta[]={
49
,
38
,
65
,
97
,
76
,
13
,
27
,
49
,
78
,
34
,
12
,
64
,
5
,
4
,
62
,
99
,
98
,
54
,
56
,
17
,
18
,
23
,
34
,
15
,
35
,
25
,
53
,
51
};?
????
int
temp=
0
;?
????
for
(
int
i=
1
;i<a.length;i++){?
???????
int
j=i-
1
;?
???????
temp=a[i];?
???????
for
(;j>=
0
&&temp<a[j];j--){?
???????
a[j+
1
]=a[j];??????????????????????
//将大于temp的值整体后移一个单位?
???????
}?
???????
a[j+
1
]=temp;?
????
}?
????
for
(
int
i=
0
;i<a.length;i++)?
???????
System.out.println(a[i]);?
}?
}
(1)基本思想:算法先将要排序的一组数按某个增量d(n/2,n为要排序数的个数)分成若干组,每组中记录的下标相差d.对每组中全部元素进行直接插入排序,然后再用一个较小的增量(d/2)对它进行分组,在每组中再进行直接插入排序。当增量减到1时,进行直接插入排序后,排序完成。
(2)实例:
(3)用java实现
?public
class
shellSort {?
public
? shellSort(){?
????
int
a[]={
1
,
54
,
6
,
3
,
78
,
34
,
12
,
45
,
56
,
100
};?
????
double
d1=a.length;?
????
int
temp=
0
;?
????
while
(
true
){?
????????
d1= Math.ceil(d1/
2
);?
????????
int
d=(
int
) d1;?
????????
for
(
int
x=
0
;x<d;x++){?
????????????
for
(
int
i=x+d;i<a.length;i+=d){?
????????????????
int
j=i-d;?
????????????????
temp=a[i];?
????????????????
for
(;j>=
0
&&temp<a[j];j-=d){?
????????????????
a[j+d]=a[j];?
????????????????
}?
????????????????
a[j+d]=temp;?
????????????
}?
????????
}?
????????
if
(d==
1
)?
????????????
break
;?
????
}?
????
for
(
int
i=
0
;i<a.length;i++)?
????????
System.out.println(a[i]);?
}?
}
(1)基本思想:在要排序的一组数中,选出最小的一个数与第一个位置的数交换;
然后在剩下的数当中再找最小的与第二个位置的数交换,如此循环到倒数第二个数和最后一个数比较为止。
(2)实例:
(3)用java实现
?public
class
selectSort {?
????
public
selectSort(){?
????????
int
a[]={
1
,
54
,
6
,
3
,
78
,
34
,
12
,
45
};?
????????
int
position=
0
;?
????????
for
(
int
i=
0
;i<a.length;i++){?
?
????????????
int
j=i+
1
;?
????????????
position=i;?
????????????
int
temp=a[i];?
????????????
for
(;j<a.length;j++){?
????????????
if
(a[j]<temp){?
????????????????
temp=a[j];?
????????????????
position=j;?
????????????
}?
????????????
}?
????????????
a[position]=a[i];?
????????????
a[i]=temp;?
????????
}?
????????
for
(
int
i=
0
;i<a.length;i++)?
????????????
System.out.println(a[i]);?
????
}?
}
(1)基本思想:堆排序是一种树形选择排序,是对直接选择排序的有效改进。
堆的定义如下:具有n个元素的序列(h1,h2,…,hn),当且仅当满足(hi>=h2i,hi>=2i+1)或(hi<=h2i,hi<=2i+1) (i=1,2,…,n/2)时称之为堆。在这里只讨论满足前者条件的堆。由堆的定义可以看出,堆顶元素(即第一个元素)必为最大项(大顶堆)。完全hashu.html" target="_blank">二叉树可以很直观地表示堆的结构。堆顶为根,其它为左子树、右子树。初始时把要排序的数的序列看作是一棵顺序存储的二叉树,调整它们的存储序,使之成为一个堆,这时堆的根节点的数最大。然后将根节点与堆的最后一个节点交换。然后对前面(n-1)个数重新调整使之成为堆。依此类推,直到只有两个节点的堆,并对它们作交换,最后得到有n个节点的有序序列。从算法描述来看,堆排序需要两个过程,一是建立堆,二是堆顶与堆的最后一个元素交换位置。所以堆排序有两个函数组成。一是建堆的渗透函数,二是反复调用渗透函数实现排序的函数。
(2)实例:
初始序列:46,79,56,38,40,84
建堆:
交换,从堆中踢出最大数
依次类推:最后堆中剩余的最后两个结点交换,踢出一个,排序完成。
(3)用java实现
?import
java.util.Arrays;?
?
public
class
HeapSort {?
?????
int
a[]={
49
,
38
,
65
,
97
,
76
,
13
,
27
,
49
,
78
,
34
,
12
,
64
,
5
,
4
,
62
,
99
,
98
,
54
,
56
,
17
,
18
,
23
,
34
,
15
,
35
,
25
,
53
,
51
};?
????
public
? HeapSort(){?
????????
heapSort(a);?
????
}?
????
public
? void
heapSort(
int
[] a){?
????????
System.out.println(
"开始排序"
);?
????????
int
arrayLength=a.length;?
????????
//循环建堆?
????????
for
(
int
i=
0
;i<arrayLength-
1
;i++){?
????????????
//建堆?
?
??????
buildMaxHeap(a,arrayLength-
1
-i);?
????????????
//交换堆顶和最后一个元素?
????????????
swap(a,
0
,arrayLength-
1
-i);?
????????????
System.out.println(Arrays.toString(a));?
????????
}?
????
}?
?
????
private
? void
swap(
int
[] data,
int
i,
int
j) {?
????????
// TODO Auto-generated method stub?
????????
int
tmp=data[i];?
????????
data[i]=data[j];?
????????
data[j]=tmp;?
????
}?
????
//对data数组从0到lastIndex建大顶堆?
????
private
void
buildMaxHeap(
int
[] data,
int
lastIndex) {?
????????
// TODO Auto-generated method stub?
????????
//从lastIndex处节点(最后一个节点)的父节点开始?
????????
for
(
int
i=(lastIndex-
1
)/
2
;i>=
0
;i--){?
????????????
//k保存正在判断的节点?
????????????
int
k=i;?
????????????
//如果当前k节点的子节点存在?
????????????
while
(k*
2
+
1
<=lastIndex){?
????????????????
//k节点的左子节点的索引?
????????????????
int
biggerIndex=
2
*k+
1
;?
????????????????
//如果biggerIndex小于lastIndex,即biggerIndex+1代表的k节点的右子节点存在?
????????????????
if
(biggerIndex<lastIndex){?
????????????????????
//若果右子节点的值较大?
????????????????????
if
(data[biggerIndex]<data[biggerIndex+
1
]){?
????????????????????????
//biggerIndex总是记录较大子节点的索引?
????????????????????????
biggerIndex++;?
????????????????????
}?
????????????????
}?
????????????????
//如果k节点的值小于其较大的子节点的值?
????????????????
if
(data[k]<data[biggerIndex]){?
????????????????????
//交换他们?
????????????????????
swap(data,k,biggerIndex);?
????????????????????
//将biggerIndex赋予k,开始while循环的下一次循环,重新保证k节点的值大于其左右子节点的值?
????????????????????
k=biggerIndex;?
????????????????
}
else
{?
????????????????????
break
;?
????????????????
}?
????????????
}
????????
}
????
}
}
(1)基本思想:在要排序的一组数中,对当前还未排好序的范围内的全部数,自上而下对相邻的两个数依次进行比较和调整,让较大的数往下沉,较小的往上冒。即:每当两相邻的数比较后发现它们的排序与排序要求相反时,就将它们互换。
(2)实例:
(3)用java实现
?public
class
bubbleSort {?
public
? bubbleSort(){?
?????
int
a[]={
49
,
38
,
65
,
97
,
76
,
13
,
27
,
49
,
78
,
34
,
12
,
64
,
5
,
4
,
62
,
99
,
98
,
54
,
56
,
17
,
18
,
23
,
34
,
15
,
35
,
25
,
53
,
51
};?
????
int
temp=
0
;?
????
for
(
int
i=
0
;i<a.length-
1
;i++){?
????????
for
(
int
j=
0
;j<a.length-
1
-i;j++){?
????????
if
(a[j]>a[j+
1
]){?
????????????
temp=a[j];?
????????????
a[j]=a[j+
1
];?
????????????
a[j+
1
]=temp;?
????????
}?
????????
}?
????
}?
????
for
(
int
i=
0
;i<a.length;i++)?
????
System.out.println(a[i]);????
}?
}
(1)基本思想:选择一个基准元素,通常选择第一个元素或者最后一个元素,通过一趟扫描,将待排序列分成两部分,一部分比基准元素小,一部分大于等于基准元素,此时基准元素在其排好序后的正确位置,然后再用同样的方法递归地排序划分的两部分。
(2)实例:
(3)用java实现
?public
class
quickSort {?
??
int
a[]={
49
,
38
,
65
,
97
,
76
,
13
,
27
,
49
,
78
,
34
,
12
,
64
,
5
,
4
,
62
,
99
,
98
,
54
,
56
,
17
,
18
,
23
,
34
,
15
,
35
,
25
,
53
,
51
};?
public
? quickSort(){?
????
quick(a);?
????
for
(
int
i=
0
;i<a.length;i++)?
????????
System.out.println(a[i]);?
}?
public
int
getMiddle(
int
[] list,
int
low,
int
high) {????
????????????
int
tmp = list[low];???
//数组的第一个作为中轴????
????????????
while
(low < high) {????
????????????????
while
(low < high && list[high] >= tmp) {????
?
??????
high--;????
????????????????
}????
????????????????
list[low] = list[high];??
//比中轴小的记录移到低端????
????????????????
while
(low < high && list[low] <= tmp) {????
????????????????????
low++;????
????????????????
}????
????????????????
list[high] = list[low];??
//比中轴大的记录移到高端????
????????????
}????
???????????
list[low] = tmp;?????????????
//中轴记录到尾????
????????????
return
low;??????????????????
//返回中轴的位置????
????????
}???
public
void
_quickSort(
int
[] list,
int
low,
int
high) {????
????????????
if
(low < high) {????
???????????????
int
middle = getMiddle(list, low, high);?
//将list数组进行一分为二????
????????????????
_quickSort(list, low, middle -
1
);???????
//对低字表进行递归排序????
???????????????
_quickSort(list, middle +
1
, high);??????
//对高字表进行递归排序????
????????????
}????
????????
}??
public
void
quick(
int
[] a2) {????
????????????
if
(a2.length >
0
) {???
//查看数组是否为空????
????????????????
_quickSort(a2,
0
, a2.length -
1
);????
????????
}????
???????
}??
}
(1)基本排序:归并(Merge)排序法是将两个(或两个以上)有序表合并成一个新的有序表,即把待排序序列分为若干个子序列,每个子序列是有序的。然后再把有序子序列合并为整体有序序列。
(2)实例:
(3)用java实现
?import
java.util.Arrays;?
?
public
class
mergingSort {?
int
a[]={
49
,
38
,
65
,
97
,
76
,
13
,
27
,
49
,
78
,
34
,
12
,
64
,
5
,
4
,
62
,
99
,
98
,
54
,
56
,
17
,
18
,
23
,
34
,
15
,
35
,
25
,
53
,
51
};?
public
? mergingSort(){?
????
sort(a,
0
,a.length-
1
);?
????
for
(
int
i=
0
;i<a.length;i++)?
????????
System.out.println(a[i]);?
}?
public
void
sort(
int
[] data,
int
left,
int
right) {?
????
// TODO Auto-generated method stub?
????
if
(left<right){?
????????
//找出中间索引?
????????
int
center=(left+right)/
2
;?
????????
//对左边数组进行递归?
????????
sort(data,left,center);?
????????
//对右边数组进行递归?
????????
sort(data,center+
1
,right);?
????????
//合并?
????????
merge(data,left,center,right);?
?
????
}?
}?
public
void
merge(
int
[] data,
int
left,
int
center,
int
right) {?
????
// TODO Auto-generated method stub?
????
int
[] tmpArr=
new
int
[data.length];?
????
int
mid=center+
1
;?
????
//third记录中间数组的索引?
????
int
third=left;?
????
int
tmp=left;?
????
while
(left<=center&&mid<=right){?
?
???
//从两个数组中取出最小的放入中间数组?
????????
if
(data[left]<=data[mid]){?
????????????
tmpArr[third++]=data[left++];?
????????
}
else
{?
????????????
tmpArr[third++]=data[mid++];?
????????
}?
????
}?
????
//剩余部分依次放入中间数组?
????
while
(mid<=right){?
????????
tmpArr[third++]=data[mid++];?
????
}?
????
while
(left<=center){?
????????
tmpArr[third++]=data[left++];?
????
}?
????
//将中间数组中的内容复制回原数组?
????
while
(tmp<=right){?
????????
data[tmp]=tmpArr[tmp++];?
????
}?
????
System.out.println(Arrays.toString(data));?
}?
?
}
(1)基本思想:将所有待比较数值(正整数)统一为同样的数位长度,数位较短的数前面补零。然后,从最低位开始,依次进行一次排序。这样从最低位排序一直到最高位排序完成以后,数列就变成一个有序序列。
(2)实例:
(3)用java实现
?import
java.util.ArrayList;?
import
java.util.List;?
?
public
class
radixSort {?
????
int
a[]={
49
,
38
,
65
,
97
,
76
,
13
,
27
,
49
,
78
,
34
,
12
,
64
,
5
,
4
,
62
,
99
,
98
,
54
,
101
,
56
,
17
,
18
,
23
,
34
,
15
,
35
,
25
,
53
,
51
};?
public
radixSort(){?
????
sort(a);?
????
for
(
int
i=
0
;i<a.length;i++)?
????????
System.out.println(a[i]);?
}?
public
? void
sort(
int
[] array){????
?
????????????
//首先确定排序的趟数;????
????????
int
max=array[
0
];????
????????
for
(
int
i=
1
;i<array.length;i++){????
???????????????
if
(array[i]>max){????
???????????????
max=array[i];????
???????????????
}????
????????????
}????
?
????
int
time=
0
;????
???????????
//判断位数;????
????????????
while
(max>
0
){????
???????????????
max/=
10
;????
????????????????
time++;????
????????????
}????
?
????????
//建立10个队列;????
????????????
List<ArrayList> queue=
new
ArrayList<ArrayList>();????
????????????
for
(
int
i=
0
;i<
10
;i++){????
????????????????
ArrayList<Integer> queue1=
new
ArrayList<Integer>();??
????????????????
queue.add(queue1);????
????????
}????
?
????????????
//进行time次分配和收集;????
????????????
for
(
int
i=
0
;i<time;i++){????
?
????????????????
//分配数组元素;????
???????????????
for
(
int
j=
0
;j<array.length;j++){????
????????????????????
//得到数字的第time+1位数;??
???????????????????
int
x=array[j]%(
int
)Math.pow(
10
, i+
1
)/(
int
)Math.pow(
10
, i);?
???????????????????
ArrayList<Integer> queue2=queue.get(x);?
???????????????????
queue2.add(array[j]);?
???????????????????
queue.set(x, queue2);?
????????????
}????
????????????????
int
count=
0
;
//元素计数器;????
????????????
//收集队列元素;????
????????????????
for
(
int
k=
0
;k<
10
;k++){??
????????????????
while
(queue.get(k).size()>
0
){?
????????????????????
ArrayList<Integer> queue3=queue.get(k);?
????????????????????????
array[count]=queue3.get(
0
);????
????????????????????????
queue3.remove(
0
);?
????????????????????
count++;?
??????????????
}????
????????????
}????
??????????
}????
?
???
}???
?
}
?
?SpringMVC+mybatis HTML5 全新高大尚后台框架_集成代码生成器