package test;
import java.util.Arrays;
public class SortTools {
/**
* 冒泡排序
*
* @param arr
*/
public static void bubbleSort(int[] arr) {
int num1 = 0;
int num2 = 0;
int num3 = 0;
boolean flag = false;
for (int i = 0; i < arr.length - 1; i++) {
num1++;
flag = false;
for (int j = 0; j < arr.length - 1 - i; j++) {
num2++;
if (arr[j] > arr[j + 1]) {
num3++;
swap(arr, j, j + 1);
flag = true;
}
}
if (!flag) {
break;
}
}
System.out.println("bubble排序次数：" + num1 + " 比较次数：" + num2 + " 改变位置次数：" + num3);
System.out.println("bubble排序后结果：" + Arrays.toString(arr));
}
/**
* 选择排序
* @param arr
*/
public static void selectSort(int[] arr) {
int num1 = 0;
int num2 = 0;
int num3 = 0;
for (int i = 0; i < arr.length - 1; i++) {
num1++;
for (int j = 1 + i; j < arr.length; j++) {
num2++;
if (arr[i] > arr[j]) {
num3++;
swap(arr, i, j);
}
}
}
System.out.println("select排序次数：" + num1 + " 比较次数：" + num2 + " 改变位置次数：" + num3);
System.out.println("select排序后结果：" + Arrays.toString(arr));
}
/**
* 插入排序
* @param arr
*/
public static void insertSort(int[] arr) {
int num1 = 0;
int num2 = 0;
int num3 = 0;
for (int i = 1; i < arr.length; i++) {
int j = i - 1;
num1++;
num2++;
int val = arr[i];
while (j >= 0 && arr[j] > val) {
num3++;
arr[j + 1] = arr[j];
j--;
}
arr[j + 1] = val;
}
System.out.println("insert排序次数：" + num1 + " 比较次数：" + num2 + " 改变位置次数：" + num3);
System.out.println("insert排序后结果：" + Arrays.toString(arr));
}
private static void swap(int[] arr, int firstIndex, int secondIndex) {
int temp = arr[firstIndex];
arr[firstIndex] = arr[secondIndex];
arr[secondIndex] = temp;
}
}
