Java数组常用方法和排序

package com.yuan;

import java.util.Arrays;

public class Practise1 {
    
    
    public static void main(String[] args){
        //数组
    
        String[] st2;
        st2 = new String[4];
        String st3[] = {"kd", "38dj"};
        String st4[] = new String[]{"123", "yui", "2k3j"};
        
        //二维数组
        int t1[][] ={{1, 3,5}, {23,44}};
        int t0[] = {1, 2, 3};
        // 替换数组元素
        Arrays.fill(t0, 9);
        Arrays.fill(t0, 0, 1, 100);
        System.out.println(t0[0]);
        //元组排序
        int t4[] = {5,3,0,12,9};
        Arrays.sort(t4);
        Arrays.sort(st3);
        System.out.println(t4[0]); //会改变原来的数组
        System.out.println(st3[0]);//根据字典排顺序排序的
        //元组复制
        int new1[] = Arrays.copyOf(t4, 3);
        int new2[] = Arrays.copyOfRange(t4, 2, 9);
        System.out.println(new1[0]+"?");
        System.out.println(new2[0]+"?");
        //数组查询
        int shuju[] = {33, 2, 44, 1, 0};
        Arrays.sort(shuju); // 如果没有进行排序结果是不确定的， 如果有多个指定的元素无法保证找到的是哪一个
        int index1 =Arrays.binarySearch(shuju, 2);//若果key在数组中返回搜索的索引值， 否则返回-1或“-"(插入点）
        int index2 =Arrays.binarySearch(shuju, 2,5, 10);
        int t2[][] = new int[2][4];
        t2[0][0] = 12; 
        for(int i=0; i<t2.length; i++){
            for(int j=0; j<t2[i].length; j++){
                System.out.print(t2[i][j]);
            }
            System.out.println();
        }
        
        
        //排序算话
        //冒泡算法
        int shuzu[] = {12,80,1,14,9,28};
        for(int i=1;i<shuzu.length;i++){
            for(int j=0;j<shuzu.length-i;j++){
                int temp;
                if(shuzu[j]>shuzu[j+1])    {
                    temp=shuzu[j];
                    shuzu[j]=shuzu[j+1];
                    shuzu[j+1]=temp;
                }
            }
        }
        System.out.println(shuzu[5]);
        
        //直接选择排序
        for(int i=1;i<shuzu.length;i++){
            int index = 0;
            for(int j=1;j<shuzu.length-i;j++){
                if(shuzu[j]>shuzu[index]){
                    index = j;
                }
                int temp = shuzu[shuzu.length-i];
                shuzu[shuzu.length-i]=shuzu[index];
                shuzu[index]=temp;
            }
        }
        System.out.println(shuzu[5]);
        
        //反转排序
        for(int j=0;j<(shuzu.length)/2;j++){
            int temp;
            if(shuzu[j]>shuzu[j+1])    {
                temp=shuzu[j];
                shuzu[j]=shuzu[(shuzu.length)/2-1-j];
                shuzu[(shuzu.length)/2-1-j]=temp;
            }
        }
        System.out.println(shuzu[5]);
    }
}