java12 ：排序

package day12;
//插入排序
import java.util.Arrays;

public class Demo01 {

public static void main(String[] args) {
int i,j,k;
int[] array = {6,2,5,7,1,3,4,9};
for (i =1;i<array.length;i++){
k = array[i];
for (j=i-1;j>=0 && array[j]>k;j--){
array[j+1] = array[j];
}
array[j+1]=k;
}
System.out.println(Arrays.toString(array));

}
}

package day12;
//冒泡排序法
import java.util.Arrays;

public class Demo02 {

public static void main(String[] args) {
int[] array = { 6, 2, 5, 7, 1, 3, 4, 9 };
for (int i = 0; i < array.length - 1; i++) {
for (int j = 0; j < array.length - i - 1; j++) {
if (array[j] > array[j + 1]) {
int t = array[j];
array[j] = array[j + 1];
array[j + 1] = t;
}
}
}
System.out.println(Arrays.toString(array));
}
}

package day12;
/**
* java的排序和冒泡排序 插入排序的比较
*很粗狂的比较，不要较真
*/
import java.util.Arrays;
import java.util.Random;

public class Demo03 {

public static void main(String[] args) {
int[] array = new int[100000];
Random random = new Random();
for (int i = 0; i < array.length; i++) {
array[i] = random.nextInt();
}
int[] array1 = Arrays.copyOf(array, array.length);
int[] array2 = Arrays.copyOf(array, array.length);
long time1 = System.currentTimeMillis();
Arrays.sort(array);
long time2 = System.currentTimeMillis();
Demo0.sort(array1);
long time3 = System.currentTimeMillis();
Demo0.sort1(array2);
long time4 = System.currentTimeMillis();
System.out.println(time2 - time1);
System.out.println(time3 - time2);
System.out.println(time4 - time3);

}

public static void sort(int[] array) {
for (int i = 0; i < array.length - 1; i++) {
for (int j = 0; j < array.length - i - 1; j++) {
if (array[j] > array[j + 1]) {
int t = array[j];
array[j] = array[j + 1];
array[j + 1] = t;
}
}
}
}

public static void sort1(int[] array) {
int i, j, k;
for (i = 1; i < array.length; i++) {
k = array[i];
for (j = i - 1; j >= 0 && array[j] > k; j--) {
array[j + 1] = array[j];
}
array[j + 1] = k;
}
}
}