1.字符串分割

public static void main(String[] args) {
          Scanner sc=new Scanner(System.in);
          while(sc.hasNext()){
              String str=sc.nextLine();
              StringBuilder sb=new StringBuilder();
              sb.append(str);
              int size=str.length();
              int addZero=8-size%8;
              while((addZero>0&&(addZero<8))){
                  sb.append("0");
                  addZero--;
              }
              String str1=sb.toString();
              while(str1.length()>0){
                  System.out.println(str1.substring(0,8));
                  str1=str1.substring(8);
              }
          }

用StringBulider进行存储，append函数补位，输出依次截取8位

2.进制转换

进制转换都能学几百遍了，还是继续不会写代码

public static void main(String[] args) throws Exception{
        Scanner sc = new Scanner(System.in);
        while(sc.hasNextLine()){
            String s = sc.nextLine();
            System.out.println(Integer.parseInt(s.substring(2,s.length()),16));
        }
    }

public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while(sc.hasNextLine()){
            String str=sc.nextLine();
            String num=str.substring(2,str.length());
            int result=0;
            int power=1;
            for (int i=num.length()-1;i>=0;i--){
                char c=num.charAt(i);
                if(c>='0'&&c<='9'){
                    result+=(c-'0')*power;
                }else if(c>='A'&&c<='F'){
                    result+=(c-'A'+10)*power;
                }
                power *=16;
            }
            System.out.println(result);
        }
        sc.close();
    }

扩展：
十进制转二进制

public static void main(String[] args) {
       int number;
       Scanner sc=new Scanner(System.in);
       ArrayList<String> binary=new ArrayList<String>();
       System.out.println("Enter a decimal number:");
       number =sc.nextInt();
       while(number!=0){
           binary.add(String.valueOf(number%2));
           number/=2;
       }
       Collections.reverse(binary);
       System.out.print("Binary number is: ");
       for(String s:binary){
           System.out.print(s);
       }