java实现各种排序算法

java实现各种排序算法

import java.util.Arrays;

public class SomeSort {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        int[] a = { 1, 5, 6, 2, 7, 4, 9 };// 升序
        // selectionSort(a);
        //bubbleSort(a);
        insertSort(a);
        System.out.println(Arrays.toString(a));
    }

    // 选择排序
    public static void selectionSort(int[] a) {

        for (int i = 0; i < a.length; i++) {
            int min = a[i], temp;
            for (int j = i; j < a.length; j++) {
                if (min > a[j]) {
                    temp = min;
                    min = a[j];
                    a[j] = temp;
                }
            }
            a[i] = min;
        }
    }

    // 冒泡排序
    public static void bubbleSort(int[] a) {
        int temp;
        for (int i = 0; i < a.length; i++) {

            for (int j = 0; j < a.length - i - 1; j++) {
                if (a[j] > a[j + 1]) {
                    temp = a[j];
                    a[j] = a[j + 1];
                    a[j + 1] = temp;
                }
            }
        }
    }
    
    //插入排序
    public static void insertSort(int[] a){
        int temp;
        for(int i = 1;i < a.length;i ++){
            for(int j = i;j > 0;j --){
                if(a[j] < a[j - 1]){
                    temp = a[j];
                    a[j] = a[j - 1];
                    a[j - 1] = temp;
                }
            }
        }
    }

    

}