算法之简单排序和冒泡排序

package PracticeTest;

import java.util.Arrays;
import java.util.Scanner;

public class Sort {

	/**
	 * @2018.08.13
	 * 算法之简单排序和冒泡排序
	 */
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		System.out.println("请输入随机数组大小len:");
		int len = scanner.nextInt();
		System.out.println("请输入随机数组范围max:");
		int max = scanner.nextInt();
		System.out.println("");
		SelectSort(len,max);
		System.out.println("");//仅为了换行，清晰
		MaoPaoPaiXu(len,max);//降序
		System.out.println("");
		MaoPaoPaiXu1(len,max);//升序
		System.out.println("");
	}
	
	public static int[]  RandomArray(int len,int max){
		int arr[] = new int[len];
		for(int i = 0;i<arr.length;i++){
			arr[i] = (int)(Math.random()*max);
		}
		System.out.println("原arr = " + Arrays.toString(arr));
	    return arr;
	}
	
	//简单排序算法
	public static int SelectSort(int len,int max){
		int arr[] = RandomArray(len,max);
		int min;
		for(int i = 0;i<arr.length -1;i++){
			for(int j =0;j<arr.length-1-i;j++){
				if(arr[j]>arr[j+1]){
					min = arr[j+1];
					arr[j+1] = arr[j];
					arr[j] = min;
				}
			}
		}
		System.out.println("arr简单排序后结果为：");
		System.out.println("arr = " + Arrays.toString(arr));
		return 0;
	}
	
	public static int MaoPaoPaiXu(int len,int max){
		int arr[] = RandomArray(len, max);
		//冒泡排序，降序
		for(int i = 0;i<arr.length-1;i++){
			for(int j = 0;j <arr.length-1-i;j++){
				if(arr[j]<arr[j+1]){
					int t = arr[j];
					arr[j] = arr[j+1];
					arr[j+1] = t;
				}
			}
		}
		System.out.println("arr冒泡排序降序后结果为：");
		System.out.println("arr = " + Arrays.toString(arr));
		return 0;
	}
	
	public static void MaoPaoPaiXu1(int len,int max){
		int arr[] = RandomArray(len, max);
		//冒泡排序，升序
		for (int k = 0; k < arr.length -1; k++) {
			for (int j = 0; j < arr.length - 1 - k; j++) {
				if (arr[j] > arr[j+1]) {
					int a = arr[j];
					arr[j] = arr[j+1];
					arr[j+1] = a;
				}
			}
		}
		System.out.println("arr冒泡排序升序后结果为：");
		System.out.println("arr = " + Arrays.toString(arr));
		return ;
	}
	
}

 

 

运行结果