java常用四种排序源代码
选择排序
public class ChooseSort {
publicstatic voidmain(String[] args) {
int[]x = { 2, 332, 16, 575, 203, 4, 23, 11, 345, 32 };
ChooseSort cs = new ChooseSort();
cs.selectSort(x);
for(int i = 0; i < x.length; i++) {
System.out.print(x[i] + " ");
}
}
publicstatic voidselectSort(int[] a) {
intminIndex = 0;
inttemp = 0;
if((a == null) || (a.length == 0))
return;
for(int i = 0; i < a.length; i++) {
minIndex = i;// 无序区的最小数据数组下标
for(int j = i + 1; j < a.length; j++) {// 在无序区中找到最小数据并保存其数组下标
if (a[j] < a[minIndex]) {
minIndex = j;
}
}
if(minIndex != i) {// 如果不是无序区的最小值位置不是默认的第一个数据，则交换之。
temp = a[i];
a[i] = a[minIndex];
a[minIndex] = temp;
}
}
}
}
插入排序
public class InsertSort {
publicstatic voidmain(String[] args) {
inta[]={ 2, 332, 16, 575, 203, 4, 23, 11, 345, 32 };;
InsertSort is=new InsertSort();
is.sort(a);
for(int i=0;i<a.length;i++){
System.out.print(a[i]+" ");
}
}
publicvoid sort(intobj[]){
for(int j=1;j<obj.length;j++){
intkey=obj[j];
inti=j-1;
while(i>=0&&obj[i]>key){
obj[i+1]=obj[i];
i--;
}
obj[i+1]=key;
}
}
}
冒泡排序
public class BubbleSort {
publicvoid bubbleSort(int a[]){
intn=a.length;
for(int i=0;i<n-1;i++){
for(int j=0;j<n-i-1;j++){
if(a[j]>a[j+1]){
int temp=a[j];
a[j]=a[j+1];
a[j+1]=temp;
}
}
}
publicstatic voidmain(String[] args){
BubbleSort bs=new BubbleSort();
inta[]={ 2, 332, 16, 575, 203, 4, 23, 11, 345, 32 };
bs.bubbleSort(a);
for(int m = 0; m < a.length; m++) {
System.out.print(a[m] + " ");
}
}
}
快速排序
public class QuickSort {
publicstatic voidmain(String[] args) {
int[]strVoid = { 2, 332,16, 575, 203, 4, 23, 11, 345, 32 };
QuickSort sort = new QuickSort();
sort.quickSort(strVoid, 0, strVoid.length - 1);
for(int m = 0; m < strVoid.length; m++) {
System.out.print(strVoid[m] + " ");
}
}
publicvoid quickSort(int strDate[], intleft, int right) {
inti, j;
i = left;
j = right;
intmiddle = strDate[(i)];
while(i < j) {
inttempDate = 0;
while(i < j && strDate[j] >= middle) {
j = j - 1;
}
tempDate = strDate[j];
strDate[j] = strDate[i];
strDate[i] = tempDate;
while(i < j && strDate[i] < middle) {
i = i + 1;
}
tempDate = strDate[j];
strDate[j] = strDate[i];
strDate[i] = tempDate;
}
strDate[i] = middle;
if(left < i - 1) {
quickSort(strDate, left, i -1);
}
if(right > i + 1) {
quickSort(strDate, i + 1,right);
}
}
}