将整数中的数字分开 - 来自Deitel的Java书籍

Question

来自Deitel＆＃34; Java How To Program＆＃34;第10版：

  

2.30（以整数分隔数字）编写一个应用程序，输入一个由用户五位数字组成的数字，将数字分成各自的数字，并将每个数字彼此分开的数字打印出来。例如，如果用户输入数字42339，程序应该打印

4   2   3   3   9

  

假设用户输入正确的位数。输入超过五位数的数字会发生什么？当您输入少于五位的数字时会发生什么？[提示：您可以使用本章中学到的技巧进行此练习。您需要同时使用分区和提醒操作来选择＆＃34;选择＆＃34;每个数字。]

有人可以向我解释我应该如何去挑选＆＃34;挑选＆＃34;使用除法和提醒操作符的个别整数？

编辑：控制结构（if / else等）尚未被允许，这些将在以后的章节中进行探讨。仅变量，算术运算符和比较运算符。

Answer 1

你知道这个数字是5位数。

怎么样？

number / 10 000 to retrieve the first digit.
number = reminder
number / 1000 to retrieve the second digit.
number = reminder
number / 100 to retrieve the third digit.
number = reminder
number / 10 to retrieve the fourth digit.
and reminder is the 5th one.

Answer 2

我对分裂的小暗示 - 你可以除以10然后看一下，那个操作是什么给... 更多，你必须推断出你是否想学习编程。

Answer 3

尝试一下：

import java.util.*;
public class DigitsDisplay
{
    public static void main (String[] args)
    {
        Scanner input = new Scanner (System.in);
        int digit;
        System.out.print("Enter a positive number: ");
        digit = input.nextInt();
        int power = 1;
        while (power <= digit) {
            power *= 10;
        }
        power /= 10;
        while (power > 0) {
            System.out.println(digit/power);
            digit %= power;
            power /= 10;
        }
    }
}

Answer 4

尝试这样的事情

String str1 = "";
int a = 12345;
while(a>0)
{
  int b = a%10;
  str1 = str1 + String.valueOf(b+" ");
  a = a/10;
}
StringBuilder str = new StringBuilder(str1);
System.out.println(str.reverse());

Answer 5

我也刚刚开始使用java和本书，这是为我做的tric的代码。请原谅我，如果我做了一些奇怪的事情......）

import java.util.Scanner;

public class SeparateNumber
{
    public static void main(String[] args)
    {
        Scanner in = new Scanner(System.in);
        int nr, nr1, nr2, nr3, nr4, nr5;

        System.out.print("Enter a number with 5 digits: ");
        nr = in.nextInt();

        nr1 = nr / 10000;
        nr2 = (nr % 10000) / 1000;
        nr3 = ((nr % 10000) % 1000) / 100;
        nr4 = (((nr % 10000) % 1000) % 100) / 10;
        nr5 = (((nr % 10000) % 1000) % 100) % 10;

        System.out.printf("%d%s%d%s%d%s%d%s%d%n", nr1, " ", nr2, " ", nr3, " ", nr4, " ", nr5);
    }
}

Answer 6

下面的代码处理在整数范围内的任何int上的拆分。

步骤：

1. 将int转换为String
2. 使用Integer.parseInt
将String的每个字符转换为int
3. 在int []
中存储int数字
4. Print int []

示例代码：

import java.util.*;

public class SplitDigits{
    public static void main(String args[]) throws Exception {
        System.out.println("Enter number:");
        Scanner sc = new Scanner(System.in);
        int number = sc.nextInt();
        System.out.println("You have entered:"+number);
        String str = String.valueOf(number);
        int length = str.length();
        if ( length > 0){
            int[] digits = new int[length];
            for ( int i=0; i < length; i++){
                digits[i] = Integer.parseInt(String.valueOf(str.charAt(i)));
            }
            for ( int i=0; i < digits.length; i++){
                System.out.println("Digits:"+digits[i]);
            }
        }

    }
}

输出：

java SplitDigits
Enter number:
123456789
You have entered:123456789
Digits:1
Digits:2
Digits:3
Digits:4
Digits:5
Digits:6
Digits:7
Digits:8
Digits:9

Answer 7

import java.util.Scanner;  
public class DigitSeparator{  
    public static void main(String[] args){  
        Scanner input = new Scanner(System.in);  
        System.out.print("Enter a 5 digit number: ");  
        int number = input.nextInt();  

        System.out.print((number / 10000)+ "   ");   
        int divider = 10000;  
        int mod = number % 10000;  

        for(int i = 1; i <= 4; i++){  
            divider /= 10;  
            System.out.print( mod/divider +"   ");  
            mod %= divider;         
        }  
        System.out.println();  
    }  
}  

Answer 8

以下是按输入顺序显示数字的答案

import java.util.Scanner;

public class oddMethod {
    public static void main(String[] args) {
        System.out.println("Enter start number:");
        int number=getNumber();
        int last=Reverse1stTime(number);
        System.out.println("Digit You Enter:"+last);
    }

    private static int getNumber() {
        Scanner sr = new Scanner(System.in);
        return sr.nextInt();
    }
    private static int Reverse1stTime(int number)
    { int  digit=0;
    int reverse=0;
        while(number>0)
        {
            digit=number%10;
            reverse=reverse*10+digit;
            number=number/10;
        }
       return reverseAgain(reverse);
    }
    private static int reverseAgain(int number)
    { int  digit=0;
        int reverse=0;
        while(number>0)
        {
            digit=number%10;
            System.out.println(digit);

            reverse=(reverse*10+digit);
            number=number/10;
        }
        return reverse;
    }
}
Input 12345
Output 12345

Answer 9

package chapter1;

import java.util.Scanner;

public class Exercise3 {

    public static void main (String[] args){
    Scanner scan = new Scanner (System.in);
    System.out.print ("Enter a number that consist of 5 digits: ");
    int num =scan.nextInt();

    int digit1 =num / 10000;
    int digit2 =(( num % 10000) / 1000 );  // the modulus answer of num/10000 is divided by 1000
    int digit3 =( ( num % 1000) / 100 );
    int digit4 = ( ( num% 100 ) / 10 );
    int digit5 = ( num % 10);

    System.out.print (digit1+"\t");
    System.out.print(digit2+"\t");
    System.out.print(digit3+"\t");
    System.out.print(digit4+"\t");
    System.out.println(digit5+"\t");
    }


}

Answer 10

答案是

//your package name

import java.util.Scanner; //for input the userin
public class SeperateDigit {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);

        System.out.printf("Enter a 5 digit number: ");
        int number = input.nextInt();

        int number1 = number/100000;
        int arrange = number%10000;
        int number2 = arrange/1000;
        int number3 = (arrange % 1000) /100;
        int number4 =(( arrange % 1000) % 100) / 10;
        int number5 = ((arrange % 1000) % 100) % 10;

        System.out.printf("%d %d %d %d %d", number1,number2,number3,number4, number5);
    }
}

结果是

Enter a 5 digit number: 422339
4 2 3 3 9