JavaSE（1）

IDEA会自带JDK，也可以配置使用自己安装的JDK

 

 

注意不可以混用

开始总想着怎么产生一组不重复的随机索引，分别分给每个数 

        Scanner sc = new Scanner(System.in);
        int[] id = new int[5];
        for (int i = 0; i < id.length; i++) {
            id[i] = sc.nextInt();
        }
        for (int i = 0; i < id.length; i++) {
            System.out.print((id[i]+"\t"));
        }
        System.out.println();
        Random rd = new Random();
        for (int i = 0; i < id.length; i++) {
            int num = rd.nextInt(5);
            int temp = id[num];
            id[num] = id[i];
            id[i] = temp;
        }
        for (int i = 0; i < id.length; i++) {
            System.out.print((id[i]+"\t"));
        }
        System.out.println();

 

        int[] a = new int[5];
        Scanner sc = new Scanner(System.in);
        Random rd = new Random();
        for (int i = 0; i < a.length; i++) {
            a[i]=rd.nextInt(20-1+1)+1;
        }
        int n = 5;
        boolean flag = false;
        for (int i = 0; i < n; i++) {
            System.out.println("输入");

            int temp = sc.nextInt();
            for (int j = 0; j < a.length; j++) {
                if(temp==a[j]){
                    System.out.println("第"+(j+1)+"个，对对了");
                    for (int k = 0; k < a.length; k++) {
                        System.out.print(a[k]+"\t");
                    }
                    flag = true;
                    break;
                }
            }
            if(flag){
                break;
            }
            if(i!=n-1) System.out.println("不对继续");
        }
        if(!flag) System.out.println("全错");

冒泡排序 

int[] a = new int[]{1,2,3,4,5,10,8,9,7,10};
        for (int i = 0; i < a.length-1; i++) { //循环length-1轮
            for (int j = 0; j < a.length-1-i; j++) { //每轮会冒出一个最大的
                if(a[j]>a[j+1]){
                    int temp = a[j];
                    a[j] = a[j+1];
                    a[j+1] = temp;
                }
            }
        }


        for (int i = 0; i < a.length; i++) {
            System.out.print(a[i]+"\t");
        }